N10-007 Domain 1: Network Concepts
Match the class of service (COS) priority on the left with its corresponding value on the right. Drag: Video (< 100ms latency) Network control Critical applications Excellent effort Best effort Internetwork control Voice (< 10ms latency) Background Drop: 0 1 2 3 4 5 6 7
0 - Background 1 - Best effort 2 - Excellent effort 3 - Critical applications 4 - Video (< 100ms latency) 5 - Voice (< 10ms latency) 6 - Internetwork control 7 - Network control Class of service (COS) marks individual frames with a priority value between 0 and 7: 0 - Background 1 - Best effort 2 - Excellent effort 3 - Critical applications 4 - Video (< 100ms latency) 5 - Voice (< 10ms latency) 6 - Internetwork control 7 - Network control
A host has the address 100.55.177.99/16. Which of the following is the broadcast address for the subnet? 100.55.255.255 255.255.255.0 100.255.255.255 100.55.177.255 255.255.0.0
100.55.255.255 EXPLANATION The broadcast address for the subnet is the last address on the subnet. In this example, the address uses 16 bits in the subnet mask (255.255.0.0), meaning that the first two octets indicate the subnet address (100.55.0.0), and the last two octets are used for host addresses. The last possible address on this subnet is 100.55.255.255.
What is the binary format for the following decimal IP address? 131.9.202.111 10000111.00001101.11001110.01011101 10000110.00001011.11000101.10101110 10000001.00001010.11000011.01010111 10000011.00001001.11001010.01101111
10000011.00001001.11001010.01101111 EXPLANATION 10000011.00001001.11001010.01101111 is the binary format of this address. To convert binary to decimal, remember the following numbers:128, 64, 32, 16, 8, 4, 2, 1Each number represents the decimal value for a binary 1 in the corresponding position. For example, 10000000 is equal to 128, and 00010000 is equal to 16. To find the binary form of a decimal number, try to subtract each decimal value from the value in the octet. For example, for 131, you can subtract 128 leaving a remainder of 3. You can then subtract 2, and then 1. For each number you can subtract, write a 1 in the address's binary position.
Which of the following use the CSMA/CD access method? 10BaseFL Token Ring 1000BaseT FDDI
1000BaseT EXPLANATION CSMA/CD stands for carrier sense multiple access/collision detection. It defines the steps network devices take when two devices attempt to use a data channel simultaneously. Ethernet networks use CSMA/CD, including 1000BaseT.
How many total channels are available for 802.11g wireless networks? 3 11 12 23 54
11 EXPLANATION 802.11b and 802.11g use the 2.4 GHz range which has a total of 11 channels in the US. 802.11a wireless uses the 5.75 GHz range which has a total of 23 channels.
Match each decimal value on the left with the corresponding hexadecimal value on the right. Not all decimal values have a corresponding hexadecimal value. Drag: 11 12 13 14 15 16 17 Drop: 11 B D F C 10
11 - 17 B - 11 D - 13 F - 15 C - 12 10 - 16 EXPLANATION Hexadecimal is a Base 16 numbering system, which means there are 16 characters possible for each number place. These characters go from 0 to 9, as decimal does; however, hexadecimal uses the letter A to represent the decimal number 10, B represents 11, and so on up to F, which represents 15.
Which data transmission rate is defined by the IEEE 802.11b wireless standard? 2 Mbps 10 Mbps 11 Mbps 56 Mbps
11 Mbps EXPLANATION The IEEE 802.11b standard defines wireless transmission rates up to 11 Mbps. Wireless network interface cards and wireless access points (also called wireless hubs or wireless routers) will automatically negotiate the best transmission speed up to 11 Mbps based on current network traffic load and the quality of the wireless connection between the client and access point. The wireless communications are affected by distance, dense physical obstructions, and other electromagnetic interference producing devices. The IEEE 802.11a standard defines wireless transmission rates up to 2 Mbps. The IEEE 802.11g standard defines wireless transmission rates up to 56 Mbps. The IEEE 802.3 standard defines Ethernet 10baseT cable based transmissions of 10 Mbps.
Assuming the network is indicated by the default portion of the IP address, which three of the following IP addresses belong to the Class A network 114.0.0.0? (Select three.) 114.58.12.0 114.122.66.12 115.0.0.66 115.88.0.55 115.77.89.4 114.0.0.15
114.58.12.0 114.122.66.12 114.0.0.15 EXPLANATION With a Class A network, the first octet indicates the network address. All hosts on the network must have the same value in the first octet (114).
You have recently installed a new Windows Server 2016 system. To ensure the accuracy of the system time, you have loaded an application that synchronizes the hardware clock on the server with an external time source on the internet. Now, you must configure the firewall on your network to allow time synchronization traffic through. Which of the following ports are you most likely to open on the firewall? 110 123 119 80
123 EXPLANATION TCP/IP port 123 is assigned to the network time protocol (NTP). NTP is used to communicate time synchronization information between systems on a network. The hypertext transfer protocol (HTTP) uses TCP/IP port 80. HTTP is the protocol used to send requests to a web server and retrieve web pages from a web server. TCP/IP port 119 is used by the network news transfer protocol (NNTP). NNTP is used to access and retrieve messages from newsgroups. TCP/IP port 110 is used by the post office protocol version 3 (POP3). POP3 is used to download email from mail servers.
Which of the following IP addresses are Class B addresses? (Select three.) 129.0.0.0 195.155.0.0 115.33.0.0 224.15.55.2 190.65.2.0 64.2.2.64 132.12.0.0
129.0.0.0 190.65.2.0 132.12.0.0 EXPLANATION The following are Class B addresses: 129.0.0.0, 132.12.0.0, and 190.65.2.0. The first octet of Class B addresses is in the range of 128 to 191.
A host on the network has an IP address of 129.11.99.78 using the default subnet mask. How would you identify the address and mask using CIDR notation? 129.11.99.78:16 129.11.99.78/8 129.11.99.78:8 129.11.99.78/24 129.11.99.78/16 129.11.99.78:24
129.11.99.78/16 EXPLANATION Use 129.11.99.78/16 for the address and the mask. With CIDR notation, follow the IP address with a slash (/) and the number of bits in the mask. The default subnet mask for this address is 255.255.0.0, which uses 16 bits in the mask. A mask value of 255.0.0.0 uses 8 bits, and a mask value of 255.255.255.0 uses 24 bits.
Your network has been assigned the Class B address of 130.15.0.0 Which of the following is not an address you can assign to a node on your network? 130.15.0.1 130.15.60.220 130.16.61.3 130.15.60.0
130.16.61.3 EXPLANATION If you plan to use the Class B address for all nodes on the network, the nodes must all have the same network address. In this case, all IP addresses must begin with 130.15.
In an IP addressing scheme that uses default subnet masks, which of the following IP addresses can you assign to a host? 127.35.88.92 132.70.254.15 127.0.0.1 199.45.207.0
132.70.254.15 EXPLANATION Addresses starting with 127 are reserved and cannot be assigned to hosts. The address 199.45.207.0 is a network ID; therefore, it is not assigned to a host.
Which of the following IP addresses is a valid IP address for a host on a public network? 142.15.6.1 10.3.125.2 192.168.16.45 172.16.254.12
142.15.6.1 EXPLANATION A public network is a network that does not limit traffic to members of a corporation or other group. The internet is an example of a public network. Certain sets of IP addresses are reserved for private networks only and cannot be used on public networks. They are: 10.0.0.0 to 10.255.255.255 172.16.0.0 to 172.31.255.255 192.168.0.0 to 192.168.255.255
Which of the following are not valid IP addresses? (Select three.) 132.64.32.8 145.8.260.7 122.0.0.0 1.55.254.3 116.0.0.116 257.0.122.55 45.22.156.256
145.8.260.7 257.0.122.55 45.22.156.256 EXPLANATION IP addresses have a value between 0 and 255 within each octet. In this list, 45.22.156.256, 145.8.260.7, and 257.0.122.55 are not valid IP addresses.
Which port number is used by SNMP? 25 110 119 143 161
161 The simple network management protocol (SNMP) uses port 161. The other listed ports are used by the following protocols: SMTP uses port 25. POP3 uses port 110. NNTP uses port 119. IMAP4 uses port 143.
Which of the following is the first IP address that can be assigned to hosts on the 166.70.0.0 network using the default subnet mask? 166.70.1.0 166.70.0.0 166.70.0.1 166.71.0.0 166.70.1.1
166.70.0.1 EXPLANATION The first address you can assign to hosts on the 166.70.0.0 network is 166.70.0.1. The network address is a Class B address and uses a default subnet mask of 255.255.0.0. The last two octets are used for host addresses. The host address range is 166.70.0.1 to 166.70.255.254. 166.70.0.0 cannot be used as a host address because it is the network address. 166.70.255.255 cannot be used as a host address because it is the broadcast address.
Which of the following is the last IP address that can be assigned to hosts on the 166.70.0.0 network using the default subnet mask? 166.70.0.254 166.70.255.255 166.71.0.0 166.70.255.254 166.70.0.255
166.70.255.254 EXPLANATION The last address you can assign to hosts on the 166.70.0.0 network is 166.70.255.254. The network address is a Class B address and uses a default subnet mask of 255.255.0.0. The last two octets are used for host addresses. 166.70.0.0 cannot be used as a host address because it is the network address. 166.70.255.255 cannot be used as a host address because it is the broadcast address.
What is the network address and subnet mask used by APIPA? (Select two.) 169.0.250.0 255.0.0.0 169.254.0.0 255.255.255.0 255.255.0.0 169.255.0.0
169.254.0.0 255.255.0.0 EXPLANATION Automatic private IP addressing (APIPA) uses a network address of 169.254.0.0 with the default Class B subnet mask of 255.255.0.0. Host addresses are within the range of 169.254.0.1 and 169.254.255.254.
Which of the following is not one of the ranges of IP addresses defined in RFC 1918 that are commonly used behind a NAT server? 192.168.0.1 - 192.168.255.254 172.16.0.1 - 172.31.255.254 10.0.0.1 - 10.255.255.254 169.254.0.1 - 169.254.255.254
169.254.0.1 - 169.254.255.254 EXPLANATION 169.254.0.1 - 169.254.255.254 is the range of IP addresses assigned to Windows DHCP clients if a DHCP server does not assign the client an IP address. This range is known as the Automatic Private IP Addressing (APIPA) range. The other three ranges listed in this question are defined as the private IP addresses from RFC 1918, which are commonly used behind a NAT server.
Which of the following IP address ranges is reserved for automatic private IP addressing? 169.168.0.1 - 169.168.255.255 169.192.0.0 - 169.192.254.255 169.254.0.1 - 169.254.255.254 192.168.0.1 - 192.168.254.255 192.168.0.0 - 192.168.255.254
169.254.0.1 - 169.254.255.254 EXPLANATION The Internet Assigned Numbers Authority (IANA) has reserved 169.254.0.1 through 169.254.255.254 for automatic private IP addressing (APIPA). APIPA also sets the subnet mask on the network to 255.255.0.0.
You've decided to use a subnet mask of 255.255.192.0 on the 172.17.0.0 network to create four separate subnets. Which network IDs will be assigned to these subnets in this configuration? (Select two.) 172.17.96.0 172.17.32.0 172.17.16.0 172.17.128.0 172.17.0.0
172.17.128.0 172.17.0.0 EXPLANATION The subnet mask used for the 172.17.0.0 network can be viewed in binary notation as 11111111.11111111.11000000.000000. Because the first two bits of the third octet are used for the network portion of the address, four subnets are possible: 172.17.0.0 172.17.64.0 172.17.128.0 172.17.192.0
Your network has been assigned the Class B network address of 179.113.0.0. Which three of the following addresses can be assigned to hosts on your network? 179.114.88.0 179.112.95.64 179.113.0.118 180.113.0.67 179.113.65.12 179.113.89.0 179.113.0.0
179.113.0.118 179.113.65.12 179.113.89.0 EXPLANATION All hosts on this network must share the first two octets of the IP address (179.113). You cannot assign 179.113.0.0 to a host because this address indicates the address of the network.
Which of the following IP addresses have a default subnet mask of 255.255.0.0? (Select all that apply.) 191.168.2.15 123.254.19.6 168.16.5.1 228.62.18.6 129.0.0.1 1.6.45.254
191.168.2.15 168.16.5.1 129.0.0.1
You have a computer that is connected to the internet through a NAT router. You want to use a private addressing scheme for your computer. Which of the following IP addresses could you assign to the computer? (Select all that apply.) 127.0.0.1 192.168.12.253 10.0.12.15 172.18.188.67 240.12.188.1 224.15.166.12 32.188.99.10
192.168.12.25 10.0.12.15 172.18.188.67 EXPLANATION Of the addresses listed here, the following are in the private IP address ranges: 10.0.12.15 (private range = 10.0.0.0 to 10.255.255.255) 172.18.188.67 (private range = 172.16.0.0 to 172.31.255.255) 192.168.12.253 (private range = 192.168.0.0 to 192.168.255.255)
You have two switches connected together as shown in the following diagram. How many broadcast domains are in the network shown? 0 1 2 4 5
2 EXPLANATION There are two broadcast domains. Each VLAN is in its own broadcast domain. When you connect devices to a switch, each switch port connection is in its own collision domain. In this graphic, there are five collision domains.
Which of the following is a valid IPv4 address? (Select two.) 192.168.1.512 2.2.2.2 10.384.0.3 256.0.0.1 1.254.1.1024 172.16.1.26 254.7.1.417
2.2.2.2 172.16.1.26 EXPLANATION A valid IPv4 address consists of four 8-bit (1 byte) numbers separated by periods (for example, 10.0.0.65). Because they are eight bits long, these numbers are frequently called octets. Even though we typically express these numbers using decimal notation, it's important to remember that they are binary numbers. The lowest value one of these numbers can have is 00000000. The decimal equivalent for this number is simply 0. The highest value one these numbers can take is 11111111. The decimal equivalent of this number is 255. Therefore, in decimal notation, each octet must contain a number between 0 and 255 inclusively.
Which of the following are frequencies defined by 802.11 committees for wireless networking? (Select two.) 700 MHz 1.9 GHz 2.4 GHz 5.75 GHz 10 GHz
2.4 GHz 5.75 GHz EXPLANATION 802.11 specifications for wireless include standards for operating in the 2.4 GHz range (802.11b, 802.11g, and 802.11n) and the 5.75 GHz range (802.11a and dual-band devices using 802.11n)
Your network has been assigned the Class C network address 200.78.151.0. Which of the following addresses can be assigned to hosts on your network? (Select three.) 200.78.151.255 200.78.152.14 200.78.151.12 200.78.151.0 200.78.151.111 200.78.151.257 200.78.151.252
200.78.151.12 200.78.151.111 200.78.151.252 EXPLANATION All hosts on this network must share the first three octets of the IP address (200.78.151). You cannot assign 200.78.151.0 to a host because this address indicates the address of the network. You cannot assign 200.78.151.255 because this address is reserved for the broadcast address.
What is the decimal format of the following binary IP address? 11001110.00111010.10101010.01000011 190.42.154.51 238.90.202.99 205.57.169.66 206.58.170.67
206.58.170.67 EXPLANATION 206.58.170.67 is the decimal form of the IP address. To convert binary to decimal, remember the following numbers:128, 64, 32, 16, 8, 4, 2, 1Each number represents the decimal value for a binary 1 in the corresponding position. For example, 10000000 is equal to 128, and 00010000 is equal to 16. To find the decimal form of a binary number, add up each decimal equivalent for each 1 bit in the address. For example, the equation for the number 11001110 is128 + 64 + 8 + 4 + 2 = 206.
Which of the following is the last IP address that can be assigned to hosts on the 211.70.0.0 network using the default subnet mask? 211.70.255.254 211.71.0.0 211.70.255.255 211.70.0.254 211.70.0.255
211.70.0.254 EXPLANATION The last address you can assign to hosts on the 211.70.0.0 network is 211.70.0.254. The network address is a Class C address and uses a default subnet mask of 255.255.255.0. The last octet is used for host addresses. 211.70.0.0 cannot be used as a host address because it is the network address. 211.70.0.255 cannot be used as a host address because it is the broadcast address.
Which of the following IP addresses are Class C addresses? (Select three.) 222.55.0.0 189.189.5.2 223.16.5.0 125.166.11.0 240.0.0.0 192.15.5.55
222.55.0.0 223.16.5.0 192.15.5.55 EXPLANATION The following are Class C addresses: 192.15.5.55, 222.55.0.0, and 223.16.5.0. The first octet of Class C addresses is in the range of 192 to 223.
How many total channels are available for 802.11a wireless networks? 3 11 12 23 54
23 EXPLANATION 802.11a wireless uses the 5.75 GHz range which has a total of 23 channels. 802.11b and 802.11g use the 2.4 GHz range which has a total of 11 channels in the US.
Which port does Telnet use? 34 25 23 80
23 EXPLANATION Telnet uses port 23.
You are configuring a network firewall to allow SMTP outbound email traffic and POP3 inbound email traffic. Which of the following TCP/IP ports should you open on the firewall? (Select two.) 21 443 25 110 143
25 110 EXPLANATION The simple mail transfer protocol (SMTP) uses TCP/IP port 25. The post office protocol version 3 (POP3) uses TCP/IP port 110. The file transfer protocol (FTP) uses TCP/IP Port 21. The internet message access protocol (IMAP) uses TCP/IP port 143. TCP/IP port 443 is used by the secure sockets layer (SSL) protocol.
You have been told to assign the IP address 21.155.67.188 to a host on the network using the default subnet mask. Which mask should you use? 21.0.0.0 255.255.0.0 255.0.0.0 21.155.0.0 255.255.255.0 21.155.67.0
255.0.0.0 EXPLANATION The default subnet mask for this address is 255.0.0.0. The address is a class A address, which begins with a number between 1 and 126 in the first octet. 21.0.0.0 is the subnet address. 255.255.0.0 is the default subnet mask for a class B address, and 255.255.255.0 is the default subnet mask for a class C address.
You are configuring the IP address for a host and have been asked to use the address 192.160.99.110/16. What subnet mask value would you use? 255.0.0.0 255.255.0.0 255.255.252.0 255.255.255.0
255.255.0.0 EXPLANATION With CIDR notation, the number of bits in the subnet mask is indicated by the /16 following the IP address. A mask that uses 16 bits is written as 255.255.0.0 in decimal format. Each octet in the mask uses 8 bits, so a mask with 16 bits uses two full octets. Use /8 for the mask 255.0.0.0 and /24 for the mask 255.255.255.0. In this example, a /24 mask would be the default subnet mask, but the address is using a non-default mask of 255.255.0.0.
What is the default subnet mask for the IP address 203.111.3.3? 255.255.255.255 255.255.255.0 255.0.0.0 255.255.0.0
255.255.255.0 EXPLANATION IP addresses are divided into classes. The most common of these are classes A, B, and C. Each address class has a different default subnet mask. To identify the class of an IP address, look at its first octet. Class A networks use a default subnet mask of 255.0.0.0 and have 0-126 as their first octet. Class B networks use a default subnet mask of 255.255.0.0 and have 128-191 as their first octet. Class C networks use a default subnet mask of 255.255.255.0 and have 192-223 as their first octet. In this question, the IP address falls in the Class C range and, therefore, has a default subnet mask of 255.255.255.0.
Which Class of Service (COS) priority value should be assigned to a video conference call? 0 7 3 4 6 1 2 5
4 EXPLANATION A priority value of 4 should be assigned to the video data stream. Each COS priority values specifies a specific traffic type: 0 - Background 1 - Best effort (default) 2 - Excellent effort 3 - Critical applications 4 - Video (< 100ms latency) 5 - Voice (< 10ms latency) 6 - Internetwork control 7 - Network control
To increase security on your company's internal network, the administrator has disabled as many ports as possible. Now, though you can browse the internet, you are unable to perform secure credit card transactions. Which port needs to be enabled to allow secure transactions? 21 69 80 443 23
443 EXPLANATION To perform secure transactions, SSL on port 443 needs to be enabled.
Which of the following tunneling methods is used to send IPv4 traffic through an IPv6 network? ISATAP 4to6 tunneling Toredo tunneling 6to4 tunneling
4to6 tunneling EXPLANATION 4to6 tunneling is used to send IPv4 traffic through an IPv6 network by encapsulating IPv4 packets within IPv6 packets. 6to4 tunneling is used to send IPv6 traffic through an IPv4 network. ISATAP is used to provide IPv6 communication over a private IPv4 network. Toredo tunneling establishes a tunnel between individual IPv6 hosts so they can communicate through a private or public IPv4 network.
What is the frequency of 802.11a networking? 900 MHz 1.2 GHz 2.4 GHz 5.75 GHz
5.75 GHz EXPLANATION 802.11a wireless operates in the 5.75 GHz range. 802.11b and 802.11g operate in the 2.4 GHz range.
You want to maintain tight security on your internal network, so you restrict access to the network through certain port numbers. If you want to allow users to continue to use DNS, which port should you enable? 443 80 53 21 42
53 EXPLANATION The DNS service uses port 53.
Which of the following are valid IPv6 IP addresses? Select all that apply. 127.0.0.1 192.168.2.15 343F:1EEE:ACDD:2034:1FF3:5012 6384:1319:7700:7631:446A:5511:8940:2552 141:0:0:0:15:0:0:1 165.15.78.53.100.1
6384:1319:7700:7631:446A:5511:8940:2552 141:0:0:0:15:0:0:1 EXPLANATION An IPv6 IP address is a 128-bit address listed as eight 16-bit hexadecimal sections. Leading zeros can be omitted in each section. Therefore, 6384:1319:7700:7631:446A:5511:8940:2552 and 141:0:0:0:15:0:0:1 are both valid IPv6 IP addresses. A single set of all-zero sections can be abbreviated with two colons (::). Therefore, 141::15:0:0:1 is also a valid address. 127.0.0.1 and 192.168.2.15 are IPv4 IP address. 343F:1EEE:ACDD:2034:1FF3:5012 is a 48 bit MAC address.
You manage a network with two locations, Portland and Seattle. Both locations are connected to the internet. All computers in both locations are configured to use IPv6. You would like to implement an IPv6 solution to meet the following requirements: Hosts in each location should be able to use IPv6 to communicate with hosts in the other location through the IPv4 internet. You want to use a site-to-site tunneling method instead of a host-to-host tunneling method. Which IPv6 solution should you use? Teredo 6to4 4to6 ISATAP
6to4 EXPLANATION Use 6to4 tunneling to create a router-to-router tunnel between two sites through an IPv4 network. Use the intra-site automatic tunnel addressing protocol (ISATAP) to enable IPv6 hosts to communicate over a private IPv4 network within a site; ISATAP does not work between sites. Use Teredo on two hosts separated by symmetric NAT to configure host-to-host tunneling. Use 4to6 tunneling to allow IPv4 traffic on an IPv6 network.
Haley configures a website using Windows Server 2016 default values. What are the HTTP port and SSL port settings? 80 for HTTP; 443 for SSL 443 for HTTP; 80 for SSL 160 for HTTP; 440 for SSL 440 for HTTP; 160 for SSL
80 for HTTP; 443 for SSL EXPLANATION The default TCP port setting for HTTP is 80. You can change that setting to another TCP setting that is not in use, but users will have to know they must request the non-default setting, or they will be unable to connect. The SSL port number is 443 and is only used with secure socket layers for encryption.
You are designing a wireless network for a client. Your client needs the network to support a data rate of at least 54 Mbps. In addition, the client already has a wireless telephone system installed that operates 2.4 GHz. Which 802.11 standard will work best in this situation? 802.11a 802.11c 802.11b 802.11g 802.11d
802.11a EXPLANATION 802.11a is the best choice for this client. While both 802.11a and 802.11g each operate at 54 Mbps, 802.11g operates in the 2.4 GHz to 2.4835 GHz range; which will cause interference with the client's wireless phone system. 802.11a, on the other hand, operates in the 5.725 GHz to 5.850 GHz frequency range; which won't interfere with the phone system.
Which IEEE wireless standards specify transmission speeds up to 54 Mbps? (Select two.) 802.11b Bluetooth 802.1x 802.11a 802.11g
802.11a 802.11g EXPLANATION Both the 802.11a and the 802.11g wireless standards specify maximum transmission speeds up to 54 Mbps. Bluetooth is a wireless standard commonly used to connect peripheral devices and operates at 720 Kbps. The 802.11b wireless standard provides transmission speeds of 11 Mbps. 802.1x is a wireless security standard that provides an authentication framework for 802-based networks.
Which IEEE standard describes wireless communication? 802.5 802.3 802.2 802.7b 802.11b
802.11b EXPLANATION One IEEE standard for wireless is 802.11b.
You are designing an update to your client's wireless network. The existing wireless network uses 802.11b equipment; which your client complains runs too slowly. She wants to upgrade the network to run up to 600 Mbps. Due to budget constraints, your client wants to upgrade only the wireless access points in the network this year. Next year, she will upgrade the wireless network boards in her users' workstations. She has also indicated that the system must continue to function during the transition period. Which 802.11 standard will work best in this situation? 802.11d 802.11a 802.11b 802.11n 802.11c
802.11n EXPLANATION 802.11n is the best choice for this client and provides up to 600 Mbps. With 802.11n, you may have a single device that uses multiple radios, one that can operate at one frequency and another that can operate on a different frequency. Because of this, 802.11n usually allows for compatibility between all 802.11 standards, depending upon the specific implementation. While 802.11g is compatible with 802.11b, it only provides up to 54 Mbps.
You are designing a wireless network for a client. Your client needs the network to support a data rate of at least 150 Mbps. In addition, the client already has a wireless telephone system installed that operates 2.4 GHz. Which 802.11 standard will work best in this situation? 802.11n 802.11a 802.11b 802.11g
802.11n EXPLANATION 802.11n is the best choice for this client. 802.11b and 802.11g both operate in the 2.4 GHz to 2.4835 GHz range, which will cause interference with the client's wireless phone system. 802.11a operates in the 5.725 GHz to 5.850 GHz frequency range. While this won't interfere with the phone system, its maximum speed is limited to 54 Mbps.
You are designing an update to your client's wireless network. The existing wireless network uses 802.11g equipment, which your client complains runs too slowly. She wants to upgrade the network to run at 150 Mbps or faster. Due to budget constraints, your client wants to upgrade only the wireless access points in the network this year. Next year, she will upgrade the wireless NICs in the workstations. She has also indicated that the system must continue to function during the transition period. Which 802.11 standard will work best in this situation? 802.11b 802.11d 802.11a 802.11n
802.11n EXPLANATION 802.11n is the best choice for this client. 802.11a operates at a maximum speed of 54 Mbps. 802.11a isn't compatible with 802.11g network boards. 802.11b runs at only 11 Mbps. 802.11n access points are backwards compatible with 802.11g equipment and run at speeds of up to 600 Mbps. Using this type of access point will allow the wireless network to continue to function during the transition.
You have been contacted by OsCorp to recommend a wireless Internet solution. The wireless strategy must support a frequency range of 5 GHz, and provide the highest possible transmission speeds. Which of the following wireless solutions would you recommend? 802.11a Bluetooth 802.11b 802.11n WEP
802.11n EXPLANATION Of the technologies listed, only the IEEE 802.11n wireless standard addresses the desired requirements. Bluetooth operates at the 2.4GHz radio frequency range and is limited to theoretical speeds of 1 to 3 Mbps and transmission distances of 33 feet. The 802.11a wireless standard offers speeds of 54 Mbps but uses the 5 GHz frequency range. 802.11b uses the 2.4 GHz frequency range but supports only 11 Mbps transfer speeds.
You are designing a wireless network for a client. Your client needs the network to support a data rate of at least 54 Mbps. In addition, the client already has a wireless telephone system installed that operates at 2.4 GHz. Which 802.11 standards will work best in this situation? (Select two.) 802.11d 802.11g 802.11n 802.11b 802.11a
802.11n 802.11a EXPLANATION 802.11a or 802.11n are the best choices for this client. While both 802.11a and 802.11g each operate at 54 Mbps, 802.11g operates in the 2.4 GHz to 2.4835 GHz range—which will cause interference with the client's wireless phone system. 802.11a and 802.11n, on the other hand, operate in the 5.725 GHz to 5.850 GHz frequency range. This won't interfere with the phone system. 802.11n can operate at speeds up to 600 Mbps.
Select the statement that best describes a broadcast storm. A broadcast storm occurs when the amount of electrical interference on a cable exceeds acceptable levels, broadcasting a storm of noise and preventing accurate data transfer. A broadcast storm occurs when a network server loses its connection to the network, and the disconnected cable sends feedback messages that overwhelm the network cable capacity. A broadcast storm occurs when there are so many broadcast messages on the network that they approach or exceed the network bandwidth. A broadcast storm occurs when the level of TCP/IP transfers overwhelm a gateway.
A broadcast storm occurs when there are so many broadcast messages on the network that they approach or exceed the network bandwidth. EXPLANATION A broadcast storm occurs when there are so many broadcast messages on the network that they approach or exceed the network bandwidth.
You connect your computer to a wireless network available at the local library. You find that you can access all the websites you want on the internet except for two. What might be causing the problem? A proxy server is blocking access to the websites. Port triggering is redirecting traffic to the wrong IP address. A firewall is blocking ports 80 and 443. The router has not been configured to perform port forwarding.
A proxy server is blocking access to the websites. EXPLANATION A proxy server can be configured to block internet access based on website or URL. Many schools and public networks use proxy servers to prevent access to websites with objectionable content. Ports 80 and 443 are used by HTTP to retrieve all web content. If a firewall were blocking these ports, access would be denied to all websites. Port forwarding directs incoming connections to a host on the private network. Port triggering dynamically opens firewall ports based on applications that initiate contact from the private network.
How does a proxy server differ from a packet filtering firewall? A proxy server operates at the Application layer, while a packet filtering firewall operates at the Network layer. A proxy server includes filters for the session ID as well as the IP address and port number. A proxy server can prevent unknown network attacks, while a packet filtering firewall can only prevent known attacks. A proxy server is used to create a DMZ, while a packet filtering firewall can only be used for screened subnets.
A proxy server operates at the Application layer, while a packet filtering firewall operates at the Network layer. EXPLANATION A proxy server is a device that stands as an intermediary between a secure private network and the public. A proxy server is an Application layer firewall that is capable of filtering by information contained within the data portion of a packet (at the Application layer). A packet filtering firewall makes decisions about which network traffic to allow by examining information in the IP packet header, such as source and destination addresses, ports, and service protocols. A packet filtering firewall operates at OSI Layer 3 (Network layer). A signature-based IDS uses patterns to detect known attacks, while an anomaly-based IDS can detect new and unknown attacks.
What is a soft phone? A traditional or VoIP phone that has a padded handset that is more comfortable for a user. A device that converts fax calls and other soft calls between the PSTN and an IP network. A software application that runs on a computer or other device that accesses a VoIP server to make real-time phone calls. A software algorithm that compresses VoIP data prior to transmission on an IP network.
A software application that runs on a computer or other device that accesses a VoIP server to make real-time phone calls. EXPLANATION A soft phone is a software application that is installed on a computing device such as a computer or a handheld device.
Which of the following does a router acting as a firewall use to control which packets are forwarded or dropped? IPsec RDP PPP VNC ACL
ACL EXPLANATION When you configure a router as a firewall, you configure the access control list (ACL) with statements that identify traffic characteristics, such as the direction of traffic (inbound or outbound), the source or destination IP address, and the port number. ACL statements include an action to either allow or deny the traffic specified by the ACL statement. IPsec is a protocol for encrypting packets. RDP and VNC are remote desktop protocols used for remotely accessing a computer's desktop. PPP is a protocol for establishing a remote access connection over a dial-up link.
Your Cisco router has three network interfaces configured: S0/1/0 is a WAN interface that is connected to an ISP. F0/0 is connected to an Ethernet LAN segment with a network address of 192.168.1.0/24. F0/1 is connected to an Ethernet LAN segment with a network address of 192.168.2.0/24. You have configured an access control list on this router using the following rules: deny ip 192.168.1.0 0.0.0.255 any deny ip 192.168.2.0 0.0.0.255 any These rules will be applied to the WAN interface on the router. Your goal is to block any IP traffic coming in on the WAN interface that has a spoofed source address that makes it appear to be coming from the two internal networks. However, when you enable the ACL, you find that no traffic is being allowed through the WAN interface. What should you do? Apply the access list to the Fa0/0 interface instead of the S0/1/0 interface. Use the outparameter instead of the inparameter within each ACL rule. Add a permitstatement to the bottom of the access list. Apply the access list to the Fa0/1 interface instead of the S0/1/0 interface.
Add a permitstatement to the bottom of the access list. EXPLANATION The problem with this access list is that it only contains deny statements. On Cisco devices, there is an implicit deny any at the end of every access list. You need to add a permit statement and identify the type of traffic that is allowed.
You have a network connected using a physical star topology. One of the drop cables connecting a workstation has been removed. Which of the following best describes what affect this will have on network communications? All devices will be able to communicate. No devices will be able to communicate. Devices on one side of the missing cable will be able to communicate with each other; devices on the other side of the missing cable will not be able to communicate. Devices on one side of the missing cable will be able to communicate with each other; devices on the other side of the missing cable will be able to communicate with each other. All devices will be able to communicate, except the device connected with the drop cable .
All devices will be able to communicate, except the device connected with the drop cable . EXPLANATION A break in a cable in a star means that the device connected to the central device (hub or switch) through that cable can no longer communicate on the network. All other hosts will be able to communicate with all other devices.
During a network infrastructure upgrade, you have replaced two 10 Mbps hubs with switches and upgraded from Category 3 UTP cable to Category 5e. During the process, you accidentally cut the Cat 5e patch cable that stretches from the network printer to the upgraded switch. What is the impact on the network? All network nodes except the printer will be available. All network nodes on the same subnet as the printer will be unavailable. All network nodes, including the printer, will be available. All network nodes connected to the switch will be unavailable. All network nodes authenticated by the same server as the printer will be unavailable.
All network nodes except the printer will be available. EXPLANATION UTP cable and switches are associated with a star network topology. In a star topology, each device is attached to the network using its own patch cable. If the cable were to fail for any reason, only the device connected by that cable would be unavailable.
Which of the following is a characteristic of static routing when compared to dynamic routing? All routes must be manually updated on the router. Routers can only use static routing when not connected to the internet. Routers send packets for destination networks to the next hop router. Routers use the hop count to identify the distance to a destination network.
All routes must be manually updated on the router. EXPLANATION Static routing requires that entries in the routing table are configured manually. Network entries remain in the routing table until manually removed. When changes to the network occur, static entries must be added or removed. The next hop router is used with most routes to identify the next router in the path to the destination, regardless of whether the route is a static or dynamically-learned route. The hop count can be used by static or dynamic routes, depending on the routing protocol used. Static routing can be used for private and public networks whether they are connected to the internet or not.
Which of the following describes how access lists can be used to improve network security? An access list filters traffic based on the frame header such as source or destination MAC address. An access list filters traffic based on the IP header information such as source or destination IP address, protocol, or socket numbers. An access list looks for patterns of traffic between multiple packets and takes action to stop detected attacks. An access list identifies traffic that must use authentication or encryption.
An access list filters traffic based on the IP header information such as source or destination IP address, protocol, or socket numbers. EXPLANATION An access list filters traffic based on the IP header information such as source or destination IP address, protocol, or socket numbers. Access lists are configured on routers and operate on Layer 3 information. Port security is configured on switches and filters traffic based on the MAC address in the frame. An intrusion detection system (IDS) or intrusion prevention system (IPS) examines patterns detected across multiple packets. An IPS can take defensive action when a suspicious pattern of traffic is detected.
Which of the following components do switches use to optimize network performance by performing switching operations in hardware rather than using the CPU and software? An application-specific integrated circuit A caching engine A traffic shaper Ethernet bonding
An application-specific integrated circuit EXPLANATION Switches use specialized hardware called an application-specific integrated circuit (ASIC), which performs switching functions in hardware rather than using the CPU and software. ASIC allows switches to perform the switching function at wire speed. Caching engines are used to store frequently accessed content for faster access; content is retrieved from the local network instead of the internet. Ethernet bonding is used to create two or more physical connections to the same network by bonding NICs or switch ports together; Ethernet bonding provides increased performance and some fault tolerance. A traffic shaper (also called a bandwidth shaper) is a device that is capable of modifying the flow of data through a network in response to network traffic conditions.
Match the networking function or device on the left with its associated OSI model layer on the right. Drag: Session ID number ASCII Port numbers Router Modem HTTP Switch Drop: Application Presentation Session Transport Network Data Link Physical
Application - HTTP Presentation - ASCII Session - Session ID number Transport - Port numbers Network - Router Data Link - Switch Physical - Modem EXPLANATION The following table describes how devices function at different layers of the OSI model. Device or Function - OSI Model Layer HTTP - Application ASCII - Presentation Session ID number - Session Port numbers - Transport Router - Network Switch - Data Link Modem - Physical
You provide internet access for a local school. You want to control internet access by user and prevent access to specific URLs. Which type of firewall should you install? IPS Circuit-level Packet filtering Application-level
Application-level EXPLANATION An application-level gateway is a firewall that is capable of filtering by information contained within the data portion of a packet. An application-level gateway can filter by user, group, and data (for example, URLs within an HTTP request). One example of an application-level gateway is a proxy server. Proxies can be configured to restrict access by user or by website. A packet filtering firewall makes decisions about which network traffic to allow by examining information in the IP packet header, such as source and destination addresses, ports, and service protocols. A circuit-level proxy, or circuit-level gateway, makes decisions about which traffic to allow based on virtual circuits or sessions. An intrusion prevention system (IPS) looks for network attacks and takes appropriate actions to stop or reduce the effects of those attacks.
You have just connected four switches as shown in the Exhibit. Assuming the default switch configuration, which switch will become the root bridge? A B C D
B EXPLANATION The switch with the lowest bridge ID becomes the root bridge. The bridge ID is composed of two parts, a bridge priority number and the MAC address assigned to the switch. The default priority number for all switches is 32,768. This means that for unconfigured switches, the switch with the lowest MAC address becomes the root bridge. In this example, bridge B has the lowest MAC address.
Which of the following routing protocols uses paths, rules, and policies instead of a metric for making routing decisions? OSPF BGP EIGRP IS-IS RIP
BGP EXPLANATION BGP is an advanced distance vector protocol (also called a path vector protocol) that uses paths, rules, and policies to make routing decisions instead of a metric
Which of the following routing protocols is used by routers on the internet for learning and sharing routes? OSPF BGP RIP IS-IS EIGRP
BGP EXPLANATION BGP is the protocol used on the internet. ISPs use BGP to identify routes between ASs. Very large networks can use BGP internally, but typically only share routes on the internet if the AS has two (or more) connections to the internet through different ISPs. RIP is used on small private networks, while OSPF and EIGRP are used on larger private networks. IS-IS is used on very large private networks and within the internet service provider (ISP) network.
A switch running STP is classified as a backup bridge. What state is it in? Blocking Disabled Forwarding Learning Listening
Blocking EXPLANATION A backup bridge is in the blocking state. It receives packets addressed specifically to it and packets addressed to all bridges. It does not forward packets or build its database.
Which of the following statements describe how VLANs affect broadcast traffic within an internetwork? (Select two.) Broadcast traffic is transmitted only within a VLAN. Devices on separate VLANs share the same subnet address. Broadcast traffic is only transmitted on VLAN1. Devices on the same VLAN have the same subnet address. Broadcast traffic is transmitted to all devices on all VLANs.
Broadcast traffic is transmitted only within a VLAN. Devices on the same VLAN have the same subnet address. EXPLANATION VLANs allow computers to be grouped into a common broadcast domain regardless of their physical location on the network. Broadcast traffic is seen only by computers belonging to the same VLAN. Devices sharing a VLAN ID must also share the same subnet address so that traffic can be routed between VLANs. Broadcast traffic is only transmitted to devices belonging to the same VLAN as the device that sent the broadcast. Broadcast traffic is not forwarded to the other VLANs.
You are building a wireless network within and between two buildings. The buildings are separated by more than 3000 feet. The wireless network should meet the following requirements: Wireless data within Building 1 should be protected with the highest degree of security. Wireless data within Building 2 should be accessible and permitted by any wireless client. Wireless signals between Buildings 1 and 2 should be protected with the highest degree of security. Wireless signals within Buildings 1 and 2 should cover the whole structure, but not extend to the outside. For each location on the image below, you need to select the following: Antenna option Security option Drag the items from the list on the left to the location identifier on the right. Items may be used more than once. Not all items will be used. Drag: WEP with PSK WPA2 with TKIP WPA2 with CCMP WEP with open authentication Omni-directional antenna Left-facing directional antenna Right-facing directional antenna Right-facing high-gain directional antenna Left-facing high-gain directional antenna Drop: Building 1 - Location A Building 1 - Location B Building 1 - Location C Building 1 - Location D Building 2 - Location A Building 2 - Location B
Building 1 - Location A Right-facing directional antenna WPA2 with CCMP Building 1 - Location B Omni-directional antenna WPA2 with CCMP Building 1 - Location C Left-facing directional antenna WPA2 with CCMP Building 1 - Location D Right-facing high-gain directional antenna WPA2 with CCMP Building 2 - Location A Omni-directional antenna WEP with open authentication Building 2 - Location B Left-facing high-gain directional antenna WPA2 with CCMP EXPLANATION To answer this question correctly, you should choose the following: Building 1 - Location A = Right-facing directional antenna, WPA2- CCMPBuilding 1 - Location B = Omni-directional antenna, WPA2- CCMPBuilding 1 - Location C = Left-facing directional antenna, WPA2- CCMPBuilding 1 - Location D = Right-facing parabolic antenna, WPA2- CCMPBuilding 2 - Location A = Omni-directional antenna, WEP with open authenticationBuilding 2 - Location B = Left-facing parabolic antenna, WPA2- CCMP Be aware of the following types of antennas: Directional antenna: Creates a narrow, focused signal in a particular direction. Focuses the signal to provide greater signal strength, thus increasing the transmission distance. Provides a stronger point-to-point connection, better equipping them to handle obstacles. A parabolic directional antenna is highly focused, sending and receiving signals in far greater distances than achieved with a typical directional antenna. Omni-directional antenna: Disperses the RF wave in an equal 360-degree pattern. Provides access to many clients in a radius. Be aware of the following types of security: Wired Equivalent Privacy (WEP) is an optional component of the 802.11 specifications, but is easily broken. When using WEP, use open authentication. Wi-Fi Protected Access 2 (WPA2) resolves the weaknesses inherent in WEP. WPA2 uses counter mode with the CBC-MAC protocol (CCMP), also known as AES-CCMP. Note that WPA2 does not use TKIP.
Which of the following topologies connects all devices to a trunk cable? Ring Tree Star Bus
Bus EXPLANATION The bus topology connects all devices to a trunk cable.
All of the 802.11 standards for wireless networking support which type of communication path sharing technology? CSMA/CD Token passing CSMA/CA Polling
CSMA/CA EXPLANATION 802.11x standards for wireless networking all support the CSMA/CA (carrier sense multiple access with collision avoidance) type of communication path sharing technology. This CSMA/CA allows multiple baseband clients to share the same communication medium. CSMA/CA works as follows: The system asks for permission to transmit. A designated authority (such as a hub, router, or access point), grants access when the communication medium is free. The system transmits data and waits for an ACK (acknowledgment). If no ACK is received, the data is retransmitted. Polling is a mechanism where one system is labeled as the primary system. The primary system polls each secondary system in turn to inquire whether they have data to transmit. Token passing is a mechanism that uses a digital pass card. Only the system holding the token is allowed to communicate. CSMA/CD is the technology used by Ethernet. CSMA/CD works as follows: The system listens for traffic. If the line is clear, the system begins transmitting. During the transmission, the system listens for collisions. If no collisions are detected, the communication succeeds. If collisions are detected, an interrupt jam signal is broadcast to stop all transmissions. Each system waits a random amount of time before starting over at step 1.
The media access control method of all Ethernet networks is __________. Token passing CSMA/CA CSMA/CD Polling
CSMA/CD EXPLANATION Carrier sense multiple access with collision detection (CSMA/CD) is the media access control method of all Ethernet networks.
Which of the following devices is used on a WAN to convert synchronous serial signals into digital signals? Modem CSU/DSU Proxy IDS
CSU/DSU EXPLANATION A CSU/DSU is a device that converts the signal received from the WAN provider into a signal that can be used by equipment at the customer site. A CSU/DSU is composed of two separate devices. The CSU terminates the digital signal and provides error correction and line monitoring. The DSU converts the digital data into synchronous serial data for connection to a router. The CSU/DSU might be two separate devices, one combined device, or integrated into a router. A modem converts digital signals to analog signals. A proxy server is a type of firewall that can filter based on upper-layer data. An intrusion detection system (IDS) is a special network device that can detect attacks and suspicious activity.
What must you install between your network and a T1 line for your network to use the T1 line? Gateway Bridge Transceiver CSU/DSU
CSU/DSU EXPLANATION A CSU/DSU is required for a network to send signals on a T1 line.
Which of the following functions are performed by proxies? (Select two.) Give users the ability to participate in real-time text-based internet discussions Filter unwanted email Cache web pages Store client files Block unwanted packets from entering your private network Block employees from accessing certain websites
Cache web pages Block employees from accessing certain websites EXPLANATION A proxy, or proxy server, stands between client computers and internet web servers. You can use a proxy server to prevent access to specific websites or to cache (save) frequently used web pages. When a proxy receives a request from the client, it checks to verify that the client is allowed access to the website. If allowed, it then checks its cache to see if the requested page is in the cache. If the page is already cached, then the proxy server fulfills the request by displaying the requested page from the cache rather than retrieving it from the internet. Receiving a web page from a local proxy server is much faster than downloading the page from the internet.
Which of the following geographic network types is made up of an interconnection of LANs? Metropolitan Area Network (MAN) Campus Area Network (CAN) Wireless Local Area Network (WLAN) Wide Area Network (WAN)
Campus Area Network (CAN) EXPLANATION A Campus Area Network (CAN) is a computer network made up of an interconnection of local area networks (LANs) within a limited geographical area, such as a university's campus. A wide area network (WAN) is a group of LANs that are geographically isolated, but are connected to form a large internetwork. A metropolitan area network (MAN) is a network that covers an area as small as a few city blocks to as large as an entire metropolitan city. A wireless LAN covers an area that is roughly the same size as a standard LAN. However, it uses radio signals instead of wires to connect systems together.
Which of the following are true about reverse proxy? (Select two.) Clients always know they are using reverse proxy. Sits between a client computer and the internet. Can perform load balancing, authentication, and caching. Handles requests from inside a private network out to the internet. Handles requests from the internet to a server in a private network.
Can perform load balancing, authentication, and caching. Handles requests from the internet to a server in a private network. EXPLANATION A reverse proxy server handles requests from the internet to a server located inside a private network. Reverse proxies can perform load balancing, authentication, and caching. Reverse proxies often work transparently, meaning clients don't know they are connected to a reverse proxy.
To optimize your network, you want to configure your wireless AP to use a channel that meets the following criteria: Non-overlapping Low utilization Low interference You performed a spectrum analysis to identify 2.4 GHz wireless channel utilization, as shown in the exhibit. (To read the spectrum analysis, imagine a line coming down from the center of the highest point of each wave. For example, the four waves whose crests are over channel 11 belong to channel 11.) Based on the results, which channel should you configure your wireless AP to use? Channel 3 Channel 11 Channel 1 Channel 8 Channel 6
Channel 1 EXPLANATION You should use channel 1. Based on the results, the only channel that meets all the criteria is channel 1. Channels 3 and 8 overlap. Channel 6 is heavily utilized and would cause issues. Channel 11 isn't used as much as channel 6, but the signal interference is much stronger.
You want to install a firewall that can reject packets that are not part of an active session. Which type of firewall should you use? Packet filtering VPN concentrator Circuit-level Application-level
Circuit-level EXPLANATION A circuit-level proxy, or circuit-level gateway, makes decisions about which traffic to allow based on virtual circuits or sessions. A circuit-level gateway: Operates at OSI Layer 5 (Session layer). Keeps a table of known connections and sessions. Packets directed to known sessions are accepted. Verifies that packets are properly sequenced. Ensures that the TCP three-way handshake process occurs only when appropriate. Does not filter packets; rather, it allows or denies sessions. A packet filtering firewall makes decisions about which network traffic to allow by examining information in the IP packet header, such as source and destination addresses, ports, and service protocols. An Application level gateway is a firewall that is capable of filtering by information contained within the data portion of a packet, such as URLs within an HTTP request. A VPN concentrator is a device that is used to establish remote access VPN connections.
Consider the following IP addresses. 124.77.8.5 131.11.0.9 190.66.250.10 196.5.89.44 Which list represents the IP address class of each listed IP address? Class B, Class C, Class C, Class D Class A, Class B, Class C, Class C Class A, Class B, Class B, Class C Class B, Class B, Class C, Class D Class B, Class B, Class C, Class C
Class A, Class B, Class B, Class C EXPLANATION The IP addresses listed are of the following classes: Class A, Class B, Class B, Class C. You can identify the IP address class by memorizing the range of values for the first octet. 0-126 = Class A 128-191 = Class B 192-223 = Class C 223-239 = Class D 240-255 = Class E
Which of the following statements about DSCP are true? (Select two.) Priority values are assigned by the network switch. Classification occurs at Layer 2. Classification occurs at Layer 3. The DiffServ field is used to add precedence values. A priority value between 0 and 7 is used.
Classification occurs at Layer 3. The DiffServ field is used to add precedence values. EXPLANATION The Differentiated Services Code Point (DSCP) classification system has the following characteristics: Classification occurs at Layer 3. Precedence values are inserted in the DiffServ field of an IP packet. Up to 64 different classifications are possible, but most networks use only the following classes: Default - best effort Expedited Forwarding (EF) - low loss, low latency Assured Forwarding (AF) - assured delivery under prescribed conditions Class Selector - maintains backward compatibility with IP Precedence field
You manage a server that uses an IP address of 192.168.255.188 with a mask of 255.255.0.0. Which of the following describes the address type? Broadcast Multicast Classful Classless Public
Classless EXPLANATION Because the IP address is not using the default subnet mask, it is using classless addressing. Classless addressing modifies the length of the subnet mask, using a custom mask value instead of the default subnet mask. Classful addressing uses the default subnet mask. Devices that only support classful addressing assume the subnet mask based on the IP address class. A broadcast address is an address that is sent to all hosts. Broadcast addresses are the last possible address on a subnet. A multicast address is an address that identifies a group of computers. Members of the group share the same multicast address. Multicast addresses are in the range of 224.0.0.0 to 239.255.255.255. A public address is an address that is registered for use on the internet.
Which of the following terms are often synonymous with or made possible with CIDR? (Select two.) NAT Classless VLSM Classful OSPF
Classless VLSM EXPLANATION Classless inter-domain routing (CIDR) allows non-default subnet masks (variable-length subnet masks, or VLSMs). Routers use the following information to identify networks: The beginning network address in the range. The number of bits used in the subnet mask. For example, the subnet 199.70.0.0 with a mask of 255.255.0.0 is represented as 199.70.0.0/16 (16 being the number of 1 bits in the subnet mask). Classful addresses rely on the IP address class to identify the subnet mask. Network address translation (NAT) allows you to connect a private network to the internet without obtaining registered addresses for every host. Private addresses are translated to the public address of the NAT router. OSPF is a routing protocol that supports CIDR features.
You have implemented a network where hosts are assigned specific roles, such as file sharing and printing roles. Other hosts access those resources, but do not host services of their own. What type of network do you have? Client-server Peer-to-peer Intranet Extranet
Client-server EXPLANATION In a client-server network, hosts have specific roles. For example, some hosts are assigned server roles, which allow them to provide network resources to other hosts. Other hosts are assigned client roles, which allow them to consume network resources. In a peer-to-peer network, each host can provide network resources to other hosts or access resources located on other hosts, and each host is in charge of controlling access to those resources. An intranet is a private network that uses internet technologies. Services on an intranet are only available to hosts that are connected to the private network. An extranet is a private network that uses internet technologies, but whose resources are made available to external (but trusted) users. For example, you might create a website on a private network that only users from a partner company can access.
When designing a firewall, what is the recommended approach for opening and closing ports? Close all ports; open only ports required by applications inside the DMZ. Close all ports. Open all ports; close ports that expose common network attacks. Close all ports; open ports 20, 21, 53, 80, and 443. Open all ports; close ports that show improper traffic or attacks in progress.
Close all ports; open only ports required by applications inside the DMZ. EXPLANATION When designing a firewall, the recommended practice is to close all ports and then only open the ports that allow the traffic that you want inside the DMZ or the private network. Ports 20, 21, 53, 80, and 443 are common ports that are opened, but the exact ports you will open depend on the services provided inside the DMZ.
You manage a network with a single switch. On each switch port, a hub connects multiple devices to the switch. Which condition are you most likely to experience on the network? Attenuation Crosstalk Interference Echo Collisions
Collisions EXPLANATION A collision occurs when two devices that share the same media segment transmit at the same time. In a switched network, collisions should only occur on ports that have multiple devices attached. To eliminate collisions, connect only a single device to each switch port. Interference is an electrical signal on a wire that is not part of the original signal sent on the wire. Common sources of interference include nearby generators, motors (such as elevator motors), radio transmitters, welders, transformers, and fluorescent lighting. Crosstalk is interference that is caused by signals within the twisted pairs of wires. Crosstalk is often introduced within connectors where the twists are removed to add the connector. Crosstalk can also occur where wires are crushed or where the plastic coating is worn. Attenuation is the loss of signal strength from one end of a cable to the other. The longer the cable, the more attenuation. Echo occurs when some of the signal is reflected back to the transmitter, distorting the signal. Echo is caused by connecting cables and devices with different impedance ratings.
Which of the following is not a reason to use subnets on a network? Improve security. Combine different media type on to the same subnet. Extend the network. Isolate network problems.
Combine different media type on to the same subnet. EXPLANATION Subnets cannot be used to combine networks of different media types on to the same subnet. Each network with a distinct media type has its own subnet. Subnets can be used to combine networks with different media types within the same internetwork.
Match each wireless term or concept on the left with its associated description on the right. Each term may be used more than once; not all descriptions have a matching term. Drag: Bounce Received signal level Signal to noise ratio Spectrum analysis Device saturation Drop: Compares the level of the Wi-Fi signal to the level of background radio signals. Checks channel utilization and identifies sources of RF inference. Identifies how strong a radio signal is at the receiver. Identifies the number of useful bits delivered from the sender to the receiver. Causes multiple copies of the same radio signal to be received by the receiving antenna. Degrades wireless network performance.
Compares the level of the Wi-Fi signal to the level of background radio signals. - Signal to noise ratio Checks channel utilization and identifies sources of RF inference. - Spectrum analysis Identifies how strong a radio signal is at the receiver. - Received signal level Identifies the number of useful bits delivered from the sender to the receiver. - blank Causes multiple copies of the same radio signal to be received by the receiving antenna. - Bounce Degrades wireless network performance. - Device saturation
Computers A and B are on the same VLAN and are separated by two switches as shown in the exhibit. Computer A sends a frame to Computer B. Which of the following best describes the composition of the frame as it travels from A to B? Computer A sends a normal frame. The first switch appends a VLAN ID to the frame. The VLAN ID remains on the frame through the second switch up to Computer B. Computer A appends a VLAN ID to the frame. It travels from switch to switch and arrives at Computer B where it removes the VLAN ID. Computer A sends a normal frame. The first switch forwards the frame to the second switch, where the VLAN ID is appended to the frame and forwarded to Computer B. Computer A sends a normal frame. The first switch appends a VLAN ID to the frame. The second switch removes the VLAN ID before forwarding it to Computer B.
Computer A sends a normal frame. The first switch appends a VLAN ID to the frame. The second switch removes the VLAN ID before forwarding it to Computer B. EXPLANATION VLAN IDs are understood only by switches and are used by switches for inter-switch traffic. The first switch appends the VLAN ID, and the second switch removes it.
You have just connected four switches as shown in the Exhibit. Assuming the default switch configuration, how can you force switch C to become the root bridge? Remove link cables 1 and 6 from the configuration. Configure a priority number of 4096 for switch C. Configure a priority number of 61440 for switch C. Remove link cable 1 from the configuration. Remove link cable 6 from the configuration.
Configure a priority number of 4096 for switch C. EXPLANATION To force a specific switch to become the root bridge, configure a priority number lower than the default (32768). The switch with the lowest bridge ID becomes the root bridge. The bridge ID is composed of two parts: a bridge priority number and the MAC address assigned to the switch. When the default priority is used for all switches, the switch with the lowest MAC address becomes the root bridge.
You have three switches configured as shown in the Exhibit. How can you guarantee that switch C becomes the root bridge? Configure switch C with a higher priority value. Configure Fa0/1 and Fa0/2 on switch C with a higher cost value. Configure switch C with a lower priority value. Configure Fa0/1 and Fa0/2 on switch C with a higher port priority. Configure Fa0/1 and Fa0/2 on switch C with a lower cost value. Configure Fa0/1 and Fa0/2 on switch C with a lower port priority.
Configure switch C with a lower priority value. EXPLANATION To guarantee that switch C becomes the root bridge, configure switch C with a lower priority value. The election of the root bridge is determined by the switch with the lowest bridge ID. The bridge ID is made of two parts: The priority value assigned to the switch. The MAC address. The switch with the lowest priority value automatically becomes the root bridge. If two or more switches have the same priority value, then the switch with the lowest MAC address becomes the root bridge. The link cost is used when determining the root port and the designated ports. The port priority is used only when there are two equal-cost paths back to the root bridge on the same switch. The port with the lowest priority is used. If two ports have the same priority, the port with the lowest port number is used.
Which of the following tasks is associated with the Session layer? Host ID number assignment Transmission synchronization Connection establishment Acknowledgement coordination
Connection establishment EXPLANATION Connection establishment is controlled through Session layer protocols.
The UDP transport protocol provides which of the following features? (Select all that apply.) Sequence numbers and acknowledgements Connectionless datagram services Guaranteed delivery Low overhead
Connectionless datagram services Low overhead EXPLANATION UDP is a connectionless protocol used by applications that need low overhead and do not require guaranteed delivery.
Which of the following prevents access based on website ratings and classifications? Content filter NIDS Packet-filtering firewall DMZ
Content filter EXPLANATION An internet content filter is software used to monitor and restrict what content is delivered to an end user across the web. Companies, schools, libraries, and families commonly use content filters to restrict internet access, block specific websites, or block specific content. A packet-filtering firewall examines the packet header information to make forwarding decisions. The firewall can accept or reject packets based on IP address, but not individual websites. A network-based IDS (NIDS) is a dedicated device installed on the network. It analyzes all traffic on the network to look for potential attacks. A demilitarized zone (DMZ) is a buffer network (or subnet) that sits between the private network and an untrusted network (such as the internet).
You have a website that uses multiple servers for different types of transactions. For example, one server is responsible for static web content, while another is responsible for secure transactions. You would like to implement a device to speed up access to your web content. The device should be able to distribute requests between the various web servers using specialized hardware, and not just a software configuration. In addition, SSL sessions should use the hardware components in the device to create the SSL sessions. Which type of device should you choose? Circuit-level gateway Bandwidth shaper Content switch Proxy server
Content switch EXPLANATION Use a content switch to perform these functions. Switches use specialized hardware modules to perform common tasks. For example, you can have a switch with a special hardware module that is used for SSL connections. Using the hardware module in a specialized switch is faster than using the CPU or software in another device. A bandwidth shaper (also called a traffic shaper) is a device that is capable of modifying the flow of data through a network in response to network traffic conditions. A proxy server is a server that sits between a client and a destination device and can be configured to filter requests based on URL. However, a proxy server uses software, not hardware to perform these tasks. A circuit-level gateway uses the session information to make filtering decisions for allowed or denied traffic.
You have a network configured to use the OSPF routing protocol. Which of the following describes the state when all OSPF routers have learned about all other routes in the network? Classful Convergence Distance vector VLSM Link state
Convergence EXPLANATION The term "convergence" is used to describe the condition when all routers have the same (or correct) routing information. Convergence requires some time, but once it is reached, it means that any router has learned about all other networks that are being advertised (or shared) on the network. Link-state and distance vector describe general methods that routers use to share routes with other routers. Classful describes a routing protocol that assumes the subnet mask based on the address class of the network. Variable length subnet masks (VLSM) lets you use custom subnet masks for subnetting or supernetting.
What is the basic purpose of the OSI Physical layer? Defines basic physical structures, such as disks. Coordinates rules for managing network servers. Coordinates rules for transmitting bits. Coordinates rules for routing packets.
Coordinates rules for transmitting bits. EXPLANATION The OSI Physical layer coordinates rules for transmitting bits.
You have a TCP/IP network with 50 hosts. There have been inconsistent communication problems between hosts. You run a protocol analyzer and discover that two hosts have the same IP address assigned. Which protocol can you implement on your network to help prevent problems such as this? IGMP ICMP SNMP IP TCP DHCP
DHCP EXPLANATION You can use the dynamic host configuration protocol (DHCP) to set up a DHCP server that will assign IP addresses automatically to network hosts. DHCP servers will not assign the same IP address to two different hosts.
You have a network with 50 workstations. You want to automatically configure workstations with the IP address, subnet mask, and default gateway values. Which device should you use? Gateway DNS server Router DHCP server
DHCP server EXPLANATION Use a DHCP server to deliver configuration information to hosts automatically. Using DHCP is easier than configuring each host manually. Use a gateway to provide access to a different network or a network that uses a different protocol. Use a router to connect multiple subnets. Use a DNS server to provide name resolution (for example, to get the IP address associated with a logical host name).
Of the following security zones, which one can serve as a buffer network between a private secured network and the untrusted internet? Extranet Padded cell Intranet DMZ
DMZ EXPLANATION A DMZ, or demilitarized zone, is a network placed between a private secured network and the untrusted internet to grant external users access to internally controlled services. The DMZ serves as a buffer network. An intranet is a private network that happens to employ internet information services. An extranet is a division of a private network that is accessible to a limited number of users, such as business partners, suppliers, and certain customers. A padded cell is an intrusion detection countermeasure used to delay intruders sufficiently to record meaningful information about them for discovery and prosecution.
Which firewall implementation creates a buffer network that can be used to host email or web servers? ACL Perimeter firewall DMZ Host-based firewall
DMZ EXPLANATION A demilitarized zone (DMZ), also called a screened subnet, is a buffer network (or subnet) that sits between the private network and an untrusted network (such as the internet). Web servers and email servers can be placed in this buffer network so that they can be accessed from the internet. Firewalls use access control lists (ACLs) to manage incoming or outgoing traffic. A perimeter firewall sits on the edge of a private network and filters all incoming and outgoing requests. A host-based firewall is used to protect a single device.
You want to implement a protocol on your network that allows computers to find the IP address of a host from a logical name. Which protocol should you implement? ARP DNS DHCP Telnet
DNS EXPLANATION DNS is a system that is distributed throughout the internetwork to provide address/name resolution. For example, the name www.mydomain.com would be identified with a specific IP address. ARP is a protocol for finding the IP address from a known MAC address. DHCP is a protocol used to assign IP addresses to hosts. Telnet is a remote management utility.
You need to enable hosts on your network to find the IP address of logical names such as srv1.myserver.com. Which device would you use? DNS server Bandwidth shaper Load balancer IPS IDS
DNS server EXPLANATION Use a DNS server to provide host-name-to-IP-address resolution. A bandwidth shaper modifies the flow of traffic to keep traffic within predefined limits. A load balancer accepts incoming client requests and distributes those requests to multiple other servers. An IDS detects security threats, while an IPS can both detect and respond to security threats.
Which wireless networking component is used to connect multiple APs together? DS IBSS BSS STA
DS EXPLANATION The distribution system (DS) is the backbone or LAN that connects multiple APs (and BSSs) together. The DS allows wireless clients to communicate with the wired network and with wireless clients in other cells. An IBSS is a set of STAs configured in ad hoc mode. A BSS, or cell, is the smallest unit of a wireless network. An STA is a wireless NIC in an end device such as a laptop or wireless PDA. The term STA often refers to the device itself, not just the NIC.
A switch is associated with which OSI model layer? Physical Data Link Transport Network
Data Link EXPLANATION Switches are associated with the Data Link layer of the OSI model. Switches examine the device address in the packet and forward messages directly to that device.
Your company purchases a new bridge that filters packets based on the MAC address of the destination computer. On which layer of the OSI model is this device functioning? Data Link Session Transport Presentation
Data Link EXPLANATION The bridge is operating at the Data Link layer.
You have just connected a new computer to your network. The network uses static IP addressing. You find that the computer can communicate with hosts on the same subnet, but not with hosts on a different subnet. No other computers are having a problem. Which of the configuration values would you most likely need to change? DNS server Default gateway IP address Subnet mask
Default gateway EXPLANATION Check the default gateway setting on the computer. The default gateway value is used for sending packets to other subnets. If the value is incorrect, then the packets will not be sent to the correct router. In this scenario, the host can communicate with other hosts on the same subnet, meaning that the IP address and subnet mask are correctly configured. The DNS server address is likely not the problem, as name resolution is not mentioned in the scenario. In addition, if name resolution were a problem, it could affect access to both local and remote hosts.
You have a small network, as shown in the Exhibit. You have configured the IP address and subnet mask on Wrk1. You want to be able to use Wrk1 to browse the internet to connect to sites like www.cisco.com. Which other parameters are required on the workstation? (Select two.) Default gateway DNS server address WINS server address DHCP server address Host name
Default gateway DNS server address EXPLANATION To access a remote network, the workstation must be configured with a default gateway address. In addition, it must be configured with one or more DNS server addresses. The DNS server address is used to contact a DNS server and find the IP address of hosts using names such as www.cisco.com. A host name is not required on the workstation to be able to contact hosts using host names on the internet. Host names are only used to identify hosts using logical names; they are not used by the device itself. If a host name is used, the computer must translate the host name (using DNS) into an IP address. A WINS server address is used for NetBIOS name resolution. This process is used on local area networks by Windows computers and is not used on the internet. A DHCP server address identifies the IP address of a DHCP server that is used to get an IP address. Most workstations automatically contact a DHCP server without having to be configured with its IP address.
Match the EtherChannel protocol on the left with its characteristics on the right. Each protocol may be used once, more than once, or not at all. Drag: Port Aggregation Protocol (PAgP) Link Aggregation Control Protocol (LACP) Drop: Desirable mode places the port in a negotiating state. Based on the 802.3ad standard. Passive mode places the port into a passive negotiating state. Auto mode places the port into a passive negotiating state. Active mode places the port in a negotiating state.
Desirable mode places the port in a negotiating state. - Port Aggregation Protocol (PAgP) Based on the 802.3ad standard. - Link Aggregation Control Protocol (LACP) Passive mode places the port into a passive negotiating state. - Link Aggregation Control Protocol (LACP) Auto mode places the port into a passive negotiating state. - Port Aggregation Protocol (PAgP) Active mode places the port in a negotiating state. - Link Aggregation Control Protocol (LACP) EXPLANATION Cisco switches can use the following protocols for EtherChannel configuration: Port Aggregation Protocol (PAgP) Port Aggregation Protocol prevents loops, limits packet loss due to misconfigured channels, and aids in network reliability. PAgP operates in the following modes: Auto places the port into a passive negotiating state and forms an EtherChannel if the port receives PAgP packets. While in this mode, the port does not initiate the negotiation. Desirable places the port in a negotiating state to form an EtherChannel by sending PAgP packets. A channel is formed with another port group in either the auto or desirable mode. Link Aggregation Control Protocol (LACP) Link Aggregation Control Protocol is based on the 802.3ad standard and has similar functions to PAgP. LACP is used when configuring EtherChannel between Cisco switches and non-Cisco switches that support 802.3ad. LACP operates in the following modes: Passive places the port into a passive negotiating state and forms an EtherChannel if the port receives LACP packets. While in this mode, the port does not initiate the negotiation. Active places the port in a negotiating state to form an EtherChannel by sending LACP packets. A channel is formed with another port group in either the active or passive mode.
You have a network connected using a full physical mesh topology. The link between device A and device B is broken. Which of the following best describes what affect this will have on network communications? Device A will be able to communicate with any device except for device B. Device A will not be able to communicate with any other device. No devices will be able to communicate with any other device. Device A will be able to communicate with all other devices.
Device A will be able to communicate with all other devices. EXPLANATION With a mesh topology, a break in a single link has no effect on communications. Data can be routed to the destination device by taking a different (sometimes longer) path through the mesh topology.
Which of the following best describes the concept of a VLAN? Devices on different networks that can receive multicast packets. Devices on the same network logically grouped as if they were on separate networks. Devices connected by a transmission medium other than cable (such as microwave or radio transmissions). Devices connected through the internet that can communicate without using a network address. Devices in separate networks (which means they have different network addresses) logically grouped as if they were in the same network.
Devices on the same network logically grouped as if they were on separate networks. EXPLANATION A VLAN is created by identifying a subset of devices on the same network and logically identifying them as if they were on separate networks. Think of a VLAN as a subdivision of a LAN.
Your wireless network consists of multiple 802.11n access points that are configured as follows: SSID (hidden): CorpNet Security: WPA2-PSK using AES Frequency: 5.7 GHz Bandwidth per channel: 20 MHz This network is required to support an ever-increasing number of devices. To ensure there is sufficient capacity, you want to maximize the available network bandwidth. What should you do? Double the bandwidth assigned per channel to 40 MHz. Implement antenna diversity. Switch to TKIP encryption. Upgrade to 802.11a access points.
Double the bandwidth assigned per channel to 40 MHz. EXPLANATION 802.11n access points provide an option to allocate double the bandwidth per channel (increasing it to 40 MHz), which results in double the data rate. The 802.11a standard only supports data rates up to 54 Mbps, which is much slower than 802.11n. Antenna diversity implements multiple antennas to combat multipath interference and improve the reliability of a wireless link; however, it does not increase throughput. TKIP is considered less secure than AES and does not increase the throughput of a wireless network.
In the output of the netstat command, you notice that a remote system has made a connection to your Windows Server 2016 system using TCP/IP port 21. Which of the following actions is the remote system most likely performing? Performing a name resolution request Downloading a web page Downloading a file Downloading email
Downloading a file EXPLANATION TCP/IP port 21 is assigned to the file transfer protocol (FTP). A system connected on this port is most likely downloading a file from an FTP server application hosted on the system. Downloading email can be achieved via a number of protocols, including the simple mail transfer protocol (SMTP), the post office protocol version 3 (POP3) and the internet message access protocol version 4 (IMAP4). SMTP uses TCP/IP port 25, while POP3 uses TCP/IP port 110, and IMAP4 uses TCP/IP port 143. Web pages are downloaded using the hypertext transfer protocol (HTTP) on TCP/IP port 80. Name resolution requests use the domain name service (DNS) protocol on TCP/IP port 53.
A router is connected to network 192.168.1.0/24 and network 192.168.2.0/24. The router is configured to use RIP and has learned of networks 192.168.3.0/24 and 192.168.4.0/24. There is no default route configured on the router. The router receives a packet addressed to network 10.1.0.0/16. What will the router do with the packet? Hold the packet in cache until a matching route is learned or configured. Send the packet to both networks 192.168.3.0 and 192.168.4.0 and to the next hop router. Drop the packet. Send the packet out both of its directly-connected networks as a broadcast frame.
Drop the packet. EXPLANATION If a packet does not match any route in a routing table, the router drops the packet. In this example, the router does not know about the destination network, and it is not configured with a default route. With a default route, the router will forward the packet to the next hop router specified by the default route.
You want to connect your small company network to the internet. Your ISP provides you with a single IP address that is to be shared between all hosts on your private network. You do not want external hosts to be able to initiate connections to internal hosts. What type of network address translation (NAT) should you implement? Static Dynamic Shared Restricted
Dynamic EXPLANATION Use dynamic NAT to share public addresses with multiple private hosts. Dynamic NAT allows private hosts to access the internet, but does not allow internet hosts to initiate contact with private hosts.
Which of the following services automatically creates and deletes host records when an IP address lease is created or released? Forward lookup Dynamic NAT DHCP Relay Dynamic DNS
Dynamic DNS EXPLANATION Dynamic DNS (DDNS) enables clients or the DHCP server to update records in the zone database automatically whenever an IP address lease is created or renewed. A forward lookup is the process of resolving a host name to an IP address. A DHCP relay is used to forward DHCP requests to a DHCP server in a different subnet. Dynamic NAT is used to automatically map internal IP addresses with a dynamic port assignment.
Which of the following routing protocols is classified as a hybrid routing protocol? RIP IS-IS OSPF EIGRP
EIGRP. EXPLANATION EIGRP is a hybrid routing protocol developed by Cisco for routing within an AS. RIP is a distance vector protocol, while OSPF and IS-IS are link state protocols.
Which technologies are used by the 802.11ac standard to increase network bandwidth? (Select two.) Four MIMO radio streams Data compression Eight MIMO radio streams 160 MHz bonded channels 40 MHz bonded channels
Eight MIMO radio streams 160 MHz bonded channels EXPLANATION To increase network bandwidth, the 802.11ac standard uses: Eight MIMO radio streams 160 MHz wide bonded channels
A new assistant network administrator was recently hired by your organization to relieve some of your workload. You assigned the assistant network administrator to replace a defective patch cable that connected port 1 on your patch panel to one of your network switches. You noticed that it took him an unusually long time to complete this task. Once done, users almost immediately began to report that the network had gone down. Upon entering the server room, you see that the assistant administrator has configured your network rack as shown in the Exhibit. What should you do? (Choose two. Each response is a complete solution.) Enable STP on each switch. Enable port security on each switch port. Remove the patch cable connecting the first switch to the third switch. Connect the patch panel to the switches with red cross-over cables. Consolidate all patch cables from the patch panel to a single switch. Replace the patch cables connecting the switches together with red cross-over cables.
Enable STP on each switch. Remove the patch cable connecting the first switch to the third switch. EXPLANATION The assistant administrator in the scenario appears to have connected the switches together in a way that creates a bridge loop (sometimes called a switching loop). Notice the following: Switch1 is connected to Switch2 and Switch3 Switch2 is connected to Switch1 and Switch3 Switch3 is connected to Switch1 and Switch2 A bridge loop occurs when there are multiple Layer 2 paths between two network hosts. This usually results in a broadcast storm as the switches repeatedly rebroadcast all broadcast messages, flooding the network. To fix this issue, you can do one of the following: Remove the patch cable connecting the first switch to the third switch. This will break the switching loop and stop the broadcast storm. Enable STP on each switch. STP ensures there is only one active path between switches. Switch ports that are part of that path are placed in a forwarding state. Switch ports that are part of redundant but unused paths are placed in a blocking (non-forwarding) state. When an active path goes down, the STP automatically recovers and activates the backup ports necessary to provide continued connectivity. Consolidating all patch cable from the patch panel to a single switch will not break the bridge loop, nor would enabling port security on each switch port. It is not necessary to replace the patch cables connecting the switches together with cross-over cables, as most switches have Auto-MDIX enabled by default.
You manage a network with multiple switches. You find that your switches are experiencing heavy broadcast storms. Which of the following will help reduce the effects of a broadcast storm? Enable spanning tree on the switches Manually set the speed for each switch port Configure each switch with a single trunk port Disable auto-duplex detection
Enable spanning tree on the switches EXPLANATION A broadcast storm is excessive broadcast traffic that renders normal network communications impossible. Broadcast storms can be caused by switching loops that cause broadcast traffic to be circulated endlessly between switches or denial of service (DoS) attacks. To reduce broadcast storms: Run the spanning tree protocol to prevent switching loops. Implement switches with built-in broadcast storm detection, which limits the bandwidth that broadcast traffic can use. Use VLANs to create separate broadcast domains on switches.
In the OSI model, which of the following functions are performed at the Presentation layer? (Select two.) Provide network services Encrypt and compress data Handle general network access, flow control, and error recovery Specify data format (such as file formats) Transmit data frames Maintain separate client connections
Encrypt and compress data Specify data format (such as file formats) The Presentation layer encrypts data, changes and converts character sets, and compresses data. File formats (such as .jpg, .wmv, and .wav) are part of the Presentation layer. The Application layer provides network services. The Session layer maintains separate client connections through session IDs and maintains those sessions. Flow control and error detection are provided at both the Transport layer and the Data Link layer. Frame transmission occurs at the Physical layer.
Which of the following functions are performed by the OSI Transport layer? (Select three.) End-to-end flow control Control media access, logical topology, and device identification Reliable message delivery Path identification and selection Consistent data formatting between dissimilar systems Format packets for delivery through the media Data segmentation and reassembly
End-to-end flow control Reliable message delivery Data segmentation and reassembly EXPLANATION The Transport layer is responsible for breaking upper-layer data into segments and allowing reliable communications through end-to-end flow control, error detection, and error correction. Message transmission through media is performed at the Physical layer. Media access, logical topology, and device identification occurs at the Data Link layer. Path identification and selection is a function of the Network layer. Data formatting is performed at the Presentation layer.
You are investigating the use of website and URL content filtering to prevent users from visiting certain websites. Which benefits are the result of implementing this technology in your organization? (Choose two.) Enforcing the organization's internet usage policy Preventing phishing attempts Identifying and disposing of infected content An increase in bandwidth availability Preventing emails containing threats
Enforcing the organization's internet usage policy An increase in bandwidth availability EXPLANATION Website filtering can be used to enforce the organization's internet usage policy and usually result in an increase in bandwidth availability. Spam blockers are used to block emails containing threats. Virus blockers identify infected content and dispose of it. Anti-phishing software scans content to identify and dispose of phishing attempts, preventing outside attempts to access confidential information.
You need to disable the FastEthernet 0/0 interface on a switch. Drag the command on the left to the appropriate configuration step on the right. It is possible that not all of the commands are required. Drag: conf t ifdown int fa0/1 shutdown speed auto show ip interface brief int disable int fa0/0 Drop: Enter global configuration mode. Enter interface configuration mode. Disable the interface. Verify that the interface is disabled.
Enter global configuration mode. - conf t Enter interface configuration mode. - int fa0/0 Disable the interface. - shutdown Verify that the interface is disabled. - show ip interface brief EXPLANATION To complete the requirements of this scenario, you need to use the following commands: Enter global configuration mode: conf t Enter interface configuration mode: int fa0/0 Disable the interface: shutdown Verify the interface status: show ip interface brief
The FastEthernet 0/0 interface on a switch is currently disabled. You need to enable it so a workstation can be connected to it. Drag the command on the left to the appropriate configuration step on the right. It is possible that not all commands are required. Drag: conf t ifup int fa0/0 shutdown no shut show interface status int enable int fa0/2 Drop: Enter global configuration mode. Enter interface configuration mode. Enable the interface. Verify that the interface is enabled.
Enter global configuration mode. - conf t Enter interface configuration mode. - int fa0/0 Enable the interface. - no shut Verify that the interface is enabled. - show interface status EXPLANATION To complete the requirements of this scenario, you need to use the following commands: Enter global configuration mode: conf t Enter interface configuration mode: int fa0/0 Enable the interface: no shut Verify the interface status: show interface status
You need to configure the FastEthernet 0/1 interface on a switch to automatically detect the appropriate link speed and duplex setting by negotiating with the device connected to the other end of the link. Drag the command on the left to the appropriate configuration step on the right. It is possible that not all of the commands are required. Drag: conf t int fa0/0 interface status int fa0/1 duplex auto speed auto duplex mixed speed full show ip interface brief Drop: Enter global configuration mode. Enter interface configuration mode. Set the speed of the interface. Set the duplex setting for the interface.
Enter global configuration mode. - conf t Enter interface configuration mode. - int fa0/1 Set the speed of the interface. - speed auto Set the duplex setting for the interface. - duplex auto EXPLANATION To complete the requirements of this scenario, you need to use the following commands: Enter global configuration mode: conf t Enter interface configuration mode: int fa0/1 Configure the interface to automatically detect the line speed: speed auto Configure the interface to automatically detect duplex settings: duplex auto
A web server on your network hosts the public website for your company. You want to make sure that a failure of the NIC in the server does not prevent the website from being accessible on the internet. Which solution should you implement? Ethernet bonding QoS Spanning tree Traffic shaping
Ethernet bonding EXPLANATION Ethernet bonding (also called NIC teaming) logically groups two or more physical connections to the same network. If one NIC fails, the second NIC with a connection to the same network can still be used. Spanning tree is a protocol on a switch that allows the switch to maintain multiple paths between switches within a subnet. A traffic shaper (also called a bandwidth shaper) is a device that is capable of modifying the flow of data through a network in response to network traffic conditions. Quality of Service (QoS) refers to a set of mechanisms that try to guarantee timely delivery or minimal delay of important or time-sensitive communications. QoS is particularly important when implementing Voice over IP (VoIP), Video over IP, or online gaming, where delay or data loss make the overall experience unacceptable.
Which of the following is a valid IPv6 address? FEC0:AB98::A7::9845:4567 FEC0:AB04:899A FEC0::AB:9007 FEC0:9087:AB04:9900:7GA2:7788:CEDF:349A 199.12.254.11
FEC0::AB:9007 EXPLANATION FEC0::AB:9007 is a valid IPv6 address. The :: in the address replaces blocks of consecutive 0s. The longer form of this address isFEC0:0000:0000:0000:0000:0000:00AB:9007. Leading 0s within a quartet can also be omitted. You can only omit one block of 0s using the double colon. Each number in the IPv6 address must be between 0-9 or A-F; G is not a valid number for the IPv6 address. An address without double colons should have a total of 32 hexadecimal numbers in eight blocks.
You want to allow users to download files from a server running the TCP/IP protocol. You want to require user authentication to gain access to specific directories on the server. Which TCP/IP protocol should you implement to provide this capability? IP HTTP FTP HTML TFTP TCP
FTP EXPLANATION You should implement the file transfer protocol (FTP). It enables file transfers and supports user authentication. The trivial file transfer protocol (TFTP) enables file transfer, but does not support user authentication.
Which of the following is likely to be located in a DMZ? User workstations Backup server Domain controller FTP server
FTP server EXPLANATION An FTP server is the most likely component from this list to be located in a DMZ (demilitarized zone) or a buffer subnet. A DMZ should only contain servers that are to be accessed by external visitors. Often it is assumed that any server placed in the DMZ will be compromised. Therefore, no mission critical or sensitive systems are located in a DMZ. A domain controller may appear in a DMZ when the DMZ is an entire isolated domain, but this practice is not common. User workstations are never located in a DMZ. Unless specifically deployed for just the DMZ, backup servers are never located in a DMZ.
You have just connected four new computer systems to an Ethernet switch using spare patch cables. After the installation, only three systems are able to access the network. You verify all client network settings and replace the network card in the failed system. The client is still unable to access the network. Which of the following might you suspect is the real cause of the problem? Incorrect LAN protocol Faulty IP stack Failed switch Incorrect routing table Failed patch cable
Failed patch cable EXPLANATION Bent and damaged patch cables will prevent client systems from accessing the network. In this scenario, a faulty patch cable is the most likely cause of the connection failure. The easiest way to test this is to simply swap out the cable and try a known working UTP patch cable.
You are moving a client to a new location within an Ethernet network. Previous to the move, the client system did not have difficulty accessing the network. During the relocation, you attach patch cables from the client system to the wall jack and from the patch panel to the switch. Once connected, you do not get a link light on the network card or the switch. You swap out the cable running between the patch panel and the switch with a known working one, but you still cannot connect. Which of the following might you suspect is the problem? Failed network card Server software configuration error Failed patch cable between the client system and the wall jack Incorrect duplex settings Faulty termination Failed switch
Failed patch cable between the client system and the wall jack EXPLANATION Because the client system previously worked in a different location, the issue is not likely related to the client system. The NIC and switch LEDs' failure to light indicate that there isn't an end-to-end connection between the client and the switch. This means that either the patch cable between the wall jack and the client is faulty or the cable between the patch panel and the switch faulty. The cable connecting the switch and the patch panel was verified, leaving the cable run between the wall jack and the client system. It is unlikely that the issue is a failed network card, as the system was functioning in a different location, eliminating the possibility of hardware and software on the client system being the problem. The failure is limited to a connection issue between a single client and a switch. If the switch failed, all clients connected to that switch would not be able to connect. Incorrect duplex settings would not prevent NIC and switch LEDs from lighting.
Which of the following are characteristics of a circuit-level gateway? (Select two.) Filters IP addresses, but not ports Filters by session Filters by URL Stateless Stateful
Filters by session Stateful EXPLANATION A circuit-level proxy or gateway makes decisions about which traffic to allow based on virtual circuits or sessions. A circuit-level proxy is considered a stateful firewall because it keeps track of the state of a session. Packet filtering firewalls are stateless and filter by on IP address and port number. Application-level gateways filter by the application layer data, which might include data such as URLs within an HTTP request.
Which of the following is the best device to deploy to protect your private network from a public untrusted network? Gateway Router Hub Firewall
Firewall EXPLANATION A firewall is the best device to deploy to protect your private network from a public untrusted network. Firewalls are used to control traffic entering and leaving your trusted network environment. Firewalls can manage traffic by source or destination IP address, port number, service protocol, application or service type, user account, and even traffic content. Routers offer some packet-based access control, but not as extensive as that of a full-fledged firewall. Hubs and gateways are not sufficient for managing the interface between a trusted network and an untrusted network.
A router is connected to network 192.168.1.0/24 and network 192.168.2.0/24. The router is configured to use RIP and has learned of networks 192.168.3.0/24 and 192.168.4.0/24. The router is also configured with a static route of 0.0.0.0 with a mask of 0.0.0.0. The router receives a packet addressed to network 10.1.0.0/16. What will the router do with the packet? Send the packet out both of its directly connected networks as a broadcast frame. Drop the packet. Forward the packet to the next hop router specified by the route to network 0.0.0.0. Send the packet out both of its directly connected networks to the next hop router.
Forward the packet to the next hop router specified by the route to network 0.0.0.0. EXPLANATION A route of 0.0.0.0 with a mask of 0.0.0.0 identifies a default route. The default route is used when no other route is a better match. Packets that match no other networks are sent to the next hop router specified by the default route.
Which of the following is true of a wireless network SSID? Is used by STAs as they roam between APs. Is a 48-bit value that identifies an AP. Allows devices to find a specific AP within an ESS. Groups wireless devices together into the same logical network.
Groups wireless devices together into the same logical network. EXPLANATION The SSID, also called the network name, groups wireless devices together into the same logical network. All devices on the same network (within the BSS and ESS) must have the same SSID. The SSID is a 32-bit value that is inserted into each frame. The SSID is case sensitive. The SSID is sometimes called the ESSID (extended service set ID) or the BSSID (basic service set ID). In practice, each term means the same thing; however, SSIDs, ESSIDs, and BSSIDs are technically different.
Which protocol is used on the World Wide Web to transmit web pages to web browsers? HTML SMTP NNTP HTTP
HTTP EXPLANATION Web servers and browsers use or hypertext transfer protocol (HTTP) , to transmit web pages on the internet. This protocol is often confused with hypertext markup language (HTML), which is used to create web content.
Which protocol is used to securely browse a website? SIP SSH HTTPS UDP ARP
HTTPS EXPLANATION HTTPS is a secure form of HTTP that uses SSL to encrypt data before it is transmitted. HTTP is used by web browsers and web servers to exchange files (such as web pages) through the World Wide Web and intranets. SSH is used for secure remote management. UDP is a data transport control protocol that does not include error correction or detection mechanisms. SIP is a protocol used by Voice over IP (VoIP) to set up and terminate phone calls. ARP is used to find the IP address of a device with a known MAC address.
You have been given a laptop to use for work. You connect the laptop to your company network, use it from home, and use it while traveling. You want to protect the laptop from internet-based attacks. Which solution should you use? Network-based firewall Host-based firewall Proxy server VPN concentrator
Host-based firewall EXPLANATION A host-based firewall inspects traffic received by a host. Use a host-based firewall to protect your computer from attacks when there is no network-based firewall, such as when you connect to the internet from a public location. A network-based firewall inspects traffic as it flows between networks. For example, you can install a network-based firewall on the edge of your private network that connects to the internet to protect your data from attacks from internet hosts. A VPN concentrator is a device connected to the edge of a private network that is used for remote access VPN connections. Remote clients establish a VPN connection to the VPN concentrator and are granted access to the private network. A proxy server is an Application layer firewall that acts as an intermediary between a secure private network and the public. Access to the public network from the private network goes through the proxy server.
Which of the following devices operates at the OSI model Layer 1? Firewall Router Switch Hub
Hub EXPLANATION A hub operates at OSI model Layer 1 (Physical layer). It regenerates electrical signals and sends those signals out all hub ports without regard to the upper-layer data. A switch operates at the OSI model Layer 2 (Data Link layer). It reads the MAC address to make frame forwarding decisions. A router and a firewall operate at OSI model Layer 3 (Network layer).
An access point that conforms to the IEEE 802.11b standard behaves similarly to what other networking device? Hub Router Gateway Terminal Patch bay
Hub EXPLANATION An access point functions like a hub by connecting multiple wireless hosts to a wired Ethernet network.
Drag the broadcast domain property on the left to the appropriate network device(s) on the right. Each property can be used more than once. Drag: Single broadcast domain Multiple broadcast domains Drop: Hub Unmanaged switch 802.11n wireless access point Router Bridge Repeater Layer 3 switch
Hub - Single broadcast domain Unmanaged switch - Single broadcast domain 802.11n wireless access point - Single broadcast domain Router - Multiple broadcast domains Bridge - Single broadcast domain Repeater - Single broadcast domain Layer 3 switch - Multiple broadcast domains EXPLANATION A broadcast domain is a logical division of a network. All network hosts within the same broadcast domain can reach each other using broadcasts at the Data Link layer. All network hosts connected to the following Layer 2 network devices are members of the same broadcast domain: Hubs Unmanaged switches (because they do not support VLANs) 802.11 wireless access points Bridges Repeaters Layer 3 devices are used to define boundaries between broadcast domains, such as a router or a layer 3 switch. A managed switch with VLANs implemented also creates separate broadcast domain for each VLAN.
Which organization is responsible for allocating public IP addresses? IANA IEEE CompTIA IETF
IANA EXPLANATION The Internet Assigned Numbers Authority (IANA) is responsible for allocating IP addresses used on the internet. When you want to obtain a public IP address, you would typically get the address from your ISP. The ISP has received addresses from a Regional Internet Registry (RIR), which was previously assigned a block of addresses from IANA. IANA is operated by the Internet Corporation for Assigned Names and Numbers (ICANN), so you might also see that ICANN is responsible for assigning public IP addresses. The IETF is an organization that is responsible for settings standards used on the internet. For example, the IETF has defined the standards for NAT as well as other protocols. The IEEE is an organization that sets networking standards for technologies such as Ethernet or wireless networking. CompTIA is a professional organization that represents computing technology companies and individuals.
Which of the following protocols allows hosts to exchange messages to indicate problems with packet delivery? ICMP IGMP IP ARP DHCP TCP
ICMP EXPLANATION The internet control message protocol (ICMP) allows hosts to exchange messages to indicate a packet's status as it travels through the network.
Which protocol does an IP host use to inform a router that it wants to receive specific multicast frames? ICMP MGP IGMP SNMP IP
IGMP EXPLANATION IP hosts use the IGMP, or internet group management protocol, to inform multicast-enabled routers that they want to receive specific multicast frames.
You have a private network connected to the internet. Your routers will not share routing information about your private network with internet routers. Which of the following best describes the type of routing protocol you would use? IGP Link state Dynamic BGP Distance vector Static
IGP EXPLANATION You would use an interior gateway protocol (IGP) on routers within your network. Routing protocols can be classified based on whether they are routing traffic within or between autonomous systems. An interior gateway protocol (IGP) routes traffic within an AS; an exterior gateway protocol (EGP) routes traffic between ASs. Link state and distance vector describe how routing protocols share routing information. The network size might determine which protocol is best for your network. Static routing uses manually-defined routes in the routing table, while dynamic routing uses a protocol so routers learn and share routes with other routers. You can use static routing, dynamic routing, or both on a private network.
Which of the following protocols stores email on the mail server and allows users to access messages from various client devices without having to download the emails? NTP IMAP4 SMTP POP3
IMAP4 EXPLANATION IMAP4 allows a mail server to store messages users can access from various locations using various client devices. A POP3 server requires the user to download his or her email. SMTP allows a user to send email to a server. The NTP protocol synchronizes the clocks of all computers on a network.
You are asked to recommend an email retrieval protocol for a company's sales team. The sales team needs to access email from various locations and possibly different computers. The sales team does not want to worry about transferring email messages or files back and forth between these computers. Which email protocol is designed for this purpose? IMAP4 POP4 POP3 SMTP MFTP
IMAP4 EXPLANATION The internet message access protocol version 4 (IMAP) is an email retrieval protocol designed to enable users to access their email from various locations without transferring messages or files back and forth between computers. Messages remain on the remote mail server and are not automatically downloaded to a client system. POP3 is an email retrieval protocol that downloads and then deletes messages from a mail server. POP3 is well suited for reading email offline, but you must go online when you want to receive and send new messages. Once your new messages have been downloaded to your computer, you can log off to read them. This option is often used when email is received over a dial-up connection.
You have a router that is configured as a firewall. The router is a Layer 3 device only. Which of the following does the router use for identifying allowed or denied packets? MAC address IP address Session ID Username and password
IP Address EXPLANATION A router acting as a firewall at Layer 3 is capable of making forwarding decisions based on the IP address. The MAC address is associated with OSI model layer 2. Switches and wireless access points use MAC addresses to control access. The session ID is used by a circuit-level gateway, and username and password are used by Application layer firewalls.
You have a router that is configured as a firewall. The router is a Layer 3 device only. Which of the following does the router use for identifying allowed or denied packets? Session ID IP address MAC address Username and password
IP address EXPLANATION A router acting as a firewall at Layer 3 is capable of making forwarding decisions based on the IP address. The MAC address is associated with OSI model Layer 2 and is used by switches and wireless access points to control access. The session ID is used by a circuit-level gateway, and usernames and passwords are used by Application layer firewalls.
You have a small network with a single subnet connected to the internet as shown in the Exhibit. The router has been assigned the two addresses shown. You need to manually configure the workstation to connect to the network. The workstation should use RouterA as the default gateway and DNS1 as the DNS server address. From the drop-down options, select the appropriate parameters to configure the workstation's TCP/IP settings. IP address 192.168.12.30 192.168.12.32 192.168.12.46 192.168.12.47 Subnet mask 255.255.255.0 225.255.255.128 255.255.255.192 255.255.255.224 255.255.255.240 255.255.255.248 255.255.255.252 Default gateway 166.11.199.77 192.168.12.34 198.162.1.22 DNS Server 166.11.199.77 192.168.12.34 198.162.1.22
IP address - 192.168.12.46 Subnet mask - 255.255.255.240 Default gateway - 192.168.12.34 DNS Server - 198.162.1.22 EXPLANATION Use the following values: Use 192.168.12.46 for the IP address. With a 28-bit mask, the router is on subnet 192.168.12.32, and valid addresses are 192.168.12.33 to 192.168.12.46. You cannot use 192.168.12.32 because it is the subnet address. You cannot use 192.168.12.47 because it is the broadcast address. A 28-bit mask is 255.255.255.240 in binary. For the default gateway address, use the address assigned to the router interface that is on the same subnet as the workstation (in this example, 192.168.12.34). For the DNS server address, use the IP address assigned to the DNS server (198.162.1.22).
You have a workstation connected to a small branch network using a single switch. The network does not have any routers and is not connected to the internet. What are the minimum configuration parameters required on the workstation to be able to communicate with all hosts on the network? IP address IP address and default gateway IP address and subnet mask IP address, subnet mask, and default gateway
IP address and subnet mask EXPLANATION On a single subnet, you only need to configure an IP address and a subnet mask. The default gateway identifies the router address used to reach remote networks. You would only use the default gateway if the network was connected to another subnet or the internet.
Which of the following routing protocols are classified as link state routing protocols? (Select two.) RIPv2 IS-IS OSPF RIP EIGRP
IS-IS OSPF EXPLANATION Both OSPF and IS-IS are link state protocols. Using the link state method, routers share only their directly-connected routes using special packets called link-state advertisements (LSAs) and link-state packets (LSPs). These route advertisements are flooded (forwarded) throughout the network. Routers use this information to build a topology database of the network. RIP and RIPv2 are classified as distance vector protocols. Using the distance vector method, routers share their entire routing table with their immediate neighbors. Routes learned from neighboring routers are added to the routing table, then shared with that router's neighbors. EIGRP is a balanced hybrid protocol. A hybrid method combines some characteristics of both the distance vector and link state methods. It shares its full routing table at startup, and partial updates take place when changes occur.
You were recently hired by a small start-up company. The company is in a small office and has several remote employees. You have been asked to find a business service that would accommodate the current size of the company, but would also be able to scale as the company grows. The service needs to provide adequate storage, as well as additional computing power. Which cloud service model should you use? PaaS SaaS DaaS IaaS
IaaS EXPLANATION Infrastructure as a service (IaaS) delivers infrastructure to the client, such as processing, storage, networks, and virtualized environments. The client deploys and runs software without purchasing servers, data center space, or network equipment. Software as a service (SaaS) delivers software applications to the client either over the internet or on a local area network. Platform as a service (PaaS) delivers everything a developer needs to build an application onto the cloud infrastructure. The deployment comes without the cost and complexity of buying and managing the underlying hardware and software layers. Data as a service (DaaS) stores and provides data from a centralized location without requiring local collection and storage.
Which of the following are included as part of Data Link layer specifications? (Select two.) Composing electrical signals as they pass through the transmission medium. Identifying physical network devices. Controlling how messages are propagated through the network. Synchronizing individual bits as they are transmitted through the network.
Identifying physical network devices. Controlling how messages are propagated through the network. EXPLANATION The Data Link layer controls device identification on networks, as well as how messages travel through the network (the logical topology). The other functions listed here are performed by the Physical layer.
Under which of the following circumstances might you implement BGP on your company network and share routes with Internet routers? If the network is connected to the Internet using public addressing. If the network is connected to the Internet using multiple ISPs. If the network has over 15 areas and uses IPv6. If the network has over 15 hops.
If the network is connected to the Internet using multiple ISPs. EXPLANATION Very large networks can use BGP internally, but typically only share routes on the Internet if the AS has two (or more) connections to the Internet through different ISPs. If your network has over 15 hops, use a routing protocol other than RIP. Use OSPF or IS-IS to divide your network into areas. Private networks that use public IP addresses do not need to share routes with Internet routers; it is typically the responsibility of the ISP to configure routes into the private network, even when public addressing is being used. A single route out of the private network is all that is required if the network has a single connection to the Internet.
You recently created a new network segment for the development department. Because the hosts are now on a different network segment, they can no longer contact the DHCP server. Both network segments are connected via a Cisco router. Which of the following would be the best action to take in order to fix the problem? Implement an IP helper address on the router. Install and configure a new DHCP server on the development network segment. Move the DHCP server to the new network segment. Configure the router to forward broadcast messages.
Implement an IP helper address on the router. EXPLANATION When an IP helper address is implemented on the Cisco router, DHCP broadcasts are forwarded to the specified IP address of the DHCP server. This allows hosts in a different network segment to contact the DHCP server. Installing and configuring a new DHCP would work, but it would not be the best solution. A new DHCP server would introduce additional costs and management overhead. Configuring the router to forward broadcast messages exposes the network to denial-of-service attacks. Moving the DHCP server would introduce the same problem to hosts in the other network segment.
Which statements accurately describe the port states of both bridges and switches? (Select two.) In the learning state, the MAC address table can be populated, but frames are not forwarded. In the learning state, all ports are in a forwarding state. Ports in a blocked state cannot receive BPDUs. In the learning state, the MAC address table cannot be populated because the port is blocked. Ports in a blocked state still receive BPDUs.
In the learning state, the MAC address table can be populated, but frames are not forwarded. Ports in a blocked state still receive BPDUs. EXPLANATION For both bridges and switches: In the learning state, ports do not forward frames, but still populate the MAC address table based on frames received. In the blocking state, ports receive BPDUs, but do not forward frames. In the listening state, all ports are blocked.
Your Windows DHCP server had a default lease time of eight days. However, you have decided to reconfigure this DHCP server to dynamically assign IP addresses to DHCP clients using a lease duration of four days. What impact, if any, will this have on the network? No impact Decreased network traffic Increased network traffic Router performance will improve Network bandwidth will increase
Increased network traffic EXPLANATION Decreasing lease time does slightly increase network traffic because clients will have to renew their IP addresses more often. However, decreasing the lease time also makes it so that you use your addresses more efficiently. There is no correlation to bandwidth increase or router performance increase.
Which of the following are reasons to configure VLANs on a switch as opposed to using switches without VLANs? (Select two.) Redundant paths between two hosts Increased number of collision domains Increased number of broadcast domains Increased security Allowing broadcast traffic between subnets
Increased number of broadcast domains Increased security EXPLANATION Create VLANs to increase the number of broadcast domains and implement security. Each VLAN is in its own broadcast domain. Broadcast traffic within the VLAN goes only to the members of the VLAN. Members of one VLAN can only communicate with members in the same VLAN through the switch. A router or a Layer 3 switch is required to enable inter-VLAN communication. Using switches increases the number of collision domains because each switch port is its own collision domain. Using VLANs does not offer this additional advantage. Spanning tree lets you have loop-free redundant paths through a switched network. Broadcast traffic does not travel between routers.
You would like to control internet access based on users, time of day, and websites visited. How can you do this? Install a proxy server. Allow internet access only through the proxy server. Configure internet zones using Internet Options. Enable Windows Firewall on each system. Add or remove exceptions to control access. Configure a packet filtering firewall. Add rules to allow or deny internet access. Configure the Local Security Policy of each system to add internet restrictions.
Install a proxy server. Allow internet access only through the proxy server. EXPLANATION Use a proxy server to control internet access based on users, time of day, and websites visited. You configure these rules on the proxy server, and all internet access requests are routed through the proxy server. Use a packet filtering firewall, such as Windows Firewall, to allow or deny individual packets based on characteristics such as source or destination address and port number. Configure internet zones to identify trusted or restricted websites and control the types of actions that can be performed when visiting those sites.
In the OSI model, which of the following functions are performed at the Application layer? (Select all that apply.) Integrating network functionality into the host operating system Enabling communication between network clients and services Conversation identification Data translation
Integrating network functionality into the host operating system Enabling communication between network clients and services EXPLANATION The Application layer enables network services and integrates network functionality into the host operating system. Applications actually run above the OSI Application layer. Conversation identification is accomplished at the Session layer through connection or transaction ID numbers. Data translation is performed at the Presentation layer.
Which two of the following statements about the dynamic host configuration protocol (DHCP) are true? It can deliver other configuration information in addition to IP addresses. It is only used to deliver IP addresses to hosts. A DHCP server assigns addresses to requesting hosts. It cannot be configured to assign the same IP address to the same host each time it boots.
It can deliver other configuration information in addition to IP addresses. A DHCP server assigns addresses to requesting hosts. EXPLANATION DHCP servers deliver IP addresses as well as other host configuration information to network hosts. DHCP can be configured to assign any available address to a host, or it can assign a specific address to a specific host.
A switch running STP is in the listening state. A message destined for a different network segment arrives at the switch. Which of the following best describes what the switch will do? It places the source address and segment in its database and forwards the message. It does not record address or segment information. It does not forward the message. It places the source address and segment in its database, but does not forward the message. It does not record address or segment information. However, the message is forwarded.
It does not record address or segment information. It does not forward the message. EXPLANATION A switch in listening state receives packets, but does not build its database or forward them. Switches in the listening state are in the process of defining their role on the network.
Which of the following are true of the IS-IS routing protocol? (Select two.) It supports IPv6 routing. It uses bandwidth and delay for the metric. A router is the boundary between one area and another. It divides large networks into areas. It is best suited for small networks. It is a classful protocol.
It supports IPv6 routing. It divides large networks into areas. EXPLANATION IS-IS is a link-state routing protocol used for routing within an AS. IS-IS is classless and uses relative link cost for the metric. Large networks are divided into areas. A network link is the boundary between one area and another area. IS-IS is best suited for large private networks.
A switch is running STP is in the learning state. A message destined for a different network segment arrives at the switch. Which of the following best describes what the switch will do? It does not record address or segment information. However, the message is forwarded. It uses the source MAC address and network segment information to build its bridge database, but does not forward the message. It does not record address or segment information. It does not forward the message. It places the source address and segment in its database and forwards the message.
It uses the source MAC address and network segment information to build its bridge database, but does not forward the message. EXPLANATION A switch in the learning state will build its database through the information it receives from incoming messages. However, it does not forward messages. Remember, devices forward messages only if they are in the forwarding state.
Which of the following cellular network types use MIMO to increase 3G data throughput? (Select two.) LTE EDGE HSPA+ CDMA2000 WiMAX
LTE HSPA+ EXPLANATION Both HSPA+ and LTE are 3G extensions that use multiple-input and multiple-output (MIMO) to increase bandwidth. EDGE was an intermediary network between 2G and 3G networks. WiMAX is a 4G specification that delivers high-speed internet service to large geographical areas. CDMA2000 is a 3G technology that adds additional traffic channels to increase bandwidth.
At which of the following OSI layers does a router operate? Layer 1 Layer 2 Layer 3 Layer 4
Layer 3 EXPLANATION A router operates at Layer 3, or the Network layer.
Which of the following are advantages of using the spanning tree protocol (STP) in network segmented bridges? (Select three.) Lets you provide redundancy by using more than one connection between devices, making your network more reliable. Prevents switching loops from forming. Calculates all the possible paths through the network and performs load balancing. Identifies the optimal path between network devices. Minimizes the convergence time required for bridges to share network information.
Lets you provide redundancy by using more than one connection between devices, making your network more reliable. Prevents switching loops from forming. Identifies the optimal path between network devices. EXPLANATION STP prevents loops in a bridged network. It allows multiple paths to exist between two devices in case of network failure. STP is the method that bridges use to configure the best path through the network. However, bridges do not maintain a map of the network. Instead, they simply identify which port should be used to forward packets. When a bridge starts up, STP runs to identify the best port. Because each bridge is configured to select the optimal port, the best path through the network is identified.
Which of the following are functions of the MAC sublayer? (Select two.) Letting devices on the network have access to the LAN Creating routing tables based on MAC addresses Mapping hardware addresses to link-layer addresses Defining a unique hardware address for each device on the network
Letting devices on the network have access to the LAN Defining a unique hardware address for each device on the network EXPLANATION The MAC sublayer defines a unique MAC or data-link address for each device on the network. This address is usually assigned by the manufacturer. The MAC sublayer also provides devices with access to the network media.
Switches running STP are in the process of exchanging BPDUs and redefining their roles. Which port state are the switches currently in? Blocking Forwarding Disabled Learning Listening
Listening EXPLANATION Switches that are exchanging STP configuration information to define their roles are in the listening state. After listening, designated bridges progress to learning and then forwarding. Backup bridges return to blocking.
Which of the following devices accepts incoming client requests and distributes those requests to specific servers? Load balancer CSU/DSU Media converter IPS Caching engine
Load balancer EXPLANATION A load balancer is a device that accepts incoming client requests and distributes those requests to multiple servers. One goal of load balancing is to distribute client requests evenly between multiple servers to improve performance. A CSU/DSU is a device that converts the signal received from the WAN provider into a signal that can be used by equipment at the customer site. An intrusion prevention system (IPS) can detect and respond to security events. A caching engine saves copies of frequently used content, eliminating the need to download the content each time it is requested. A media converter converts signals used on one media type (such as twisted pair Ethernet) to another media type (such as fiber optic).
The Data Link Layer of the OSI model is comprised of two sublayers. What are they? (Select two.) MAC LLC LAT SAN DLC
MAC LLC EXPLANATION The Data Link layer is split into the following sublayers: The Logical Link Control (LLC) Sublayer, which provides the operating system link to the device driver. The Media Access Control (MAC) Sublayer, which translates generic network requests into device-specific terms.
You have a router configured to share routing information using RIP. In addition, you have a single static route that identifies a default route for all other networks. The next hop router for the default route has changed. You need to make the change with the least amount of effort possible. What should you do? Wait for network convergence to take place. Manually reconfigure the default route to point to the new next hop router. Force RIP to perform an immediate update. Stop and restart the RIP protocol on the router.
Manually reconfigure the default route to point to the new next hop router. EXPLANATION With a static route, when changes to the network occur, routing table entries must be modified, added, or removed manually. In this example, the default route was configured manually, so it must be manually updated. When using a routing protocol, routing changes are made automatically by routers sharing routing information. To make a change for a dynamic route, simply wait for convergence to occur (the term convergence describes the condition when all routers have the same routing information).
You want to implement a fault tolerant topology as you connect routers on your wide area network. Which of the following topologies meets your needs? Bus Ring Mesh Star
Mesh EXPLANATION A mesh topology has multiple connections at each node, increasing connectivity fault tolerance. None of the other topologies have native fault tolerance built in.
Your manager has asked you to implement a network infrastructure that will accommodate failed connections. Which of the following network topologies provides redundancy for a failed link? Bus Star Ring Mesh
Mesh EXPLANATION In a mesh topology, each network device is interconnected to all other network nodes. This creates multiple data paths. If a link fails, the data has an alternate route to its destination. The star topology connects network devices to the network with a single patch cable. A patch cable failure makes the connected device unavailable. The bus topology has a single point of failure. If there is a break in the network media, the network becomes unavailable. A single break in a physical ring topology disables the network.
You have implemented an ad hoc wireless network that doesn't employ a wireless access point. Every wireless network card can communicate directly with any other wireless network card on the network. What type of physical network topology has been implemented in this type of network? Star Ring Bus Tree Mesh
Mesh EXPLANATION This type of network uses a physical mesh topology. A mesh topology has two key characteristics: There is no central connecting point. Any host can communicate directly with any other host on the network. A mesh network is usually impractical on a wired network. Each host would require a separate dedicated network interface and cable connected to each host on the network. But you can implement a mesh topology with relative ease on a wireless network because wires aren't an issue.
You have a network that uses a logical bus topology. How do messages travel through the network? Messages are broadcast to all devices connected to the network. Messages are sent to a central device that forwards them to the destination devices. Messages are sent directly to the correct destination device. Messages travel from one device to the next until they reach the destination device.
Messages are broadcast to all devices connected to the network. EXPLANATION Messages sent using a physical bus topology are broadcast to all devices in the network. The device in the middle of the star, which is typically a hub, receives the message and forwards it on to all other devices.
You have a network that uses a logical ring topology. How do messages travel through the network? Messages are sent to a central device that forwards them to the destination devices. Messages are sent directly to the destination device only. Messages are sent to all devices connected to the network. Messages travel from one device to the next until they reach the destination device.
Messages travel from one device to the next until they reach the destination device. EXPLANATION In a logical ring topology, messages travel to each device in turn. If the message is not intended for that device, the message is forwarded to the next device on the network.
When multiple routes to a destination exist, what is used to select the best possible route? Exterior gateway protocol Distance vector Autonomous system number Metric
Metric EXPLANATION Routers use metric values to identify the distance, or cost, to a destination network. The metric is used by the routing protocol to identify and select the best route to the destination when multiple routes exist. The metric can be calculated based on hop count, bandwidth, or link cost. The Exterior Gateway Protocol is a routing protocol that routes traffic between autonomous systems. The distance vector is a routing protocol that defines how routers update and share routing information. An autonomous system number is a unique number used to identify an autonomous system.
Which of the following geographic network types are typically managed by a city as a public utility? Wide area network (WAN) Metropolitan area network (MAN) Personal area network (PAN) Local area network (LAN)
Metropolitan area network (MAN) EXPLANATION A metropolitan area network (MAN) is a network that can cover an entire city. A city typically owns and manages a MAN as a public utility. A PAN is a small network for communication between personal devices. A LAN is contained to an office and managed by a business. A WAN is a collection of LANs that are connected together to form a large internetwork; WAN connections are typically managed by an ISP.
You have a server at work with a custom application installed. Connections to the server that use the custom application must use IPv6. The server is currently running IPv4. You are the only person who connects to the server, and you always use your Linux laptop for the connection. Your laptop supports both IPv4 and IPv6. The rest of your company network runs only IPv4. You need a cost-effective solution to allow your laptop to connect to the server. Your solution must also support communication through NAT servers. Which client software should you use to connect to the server? Miredo ISATAP 6to4 4to6
Miredo EXPLANATION On Linux, Miredo client software is used to implement Teredo tunneling. Teredo tunneling establishes a tunnel between individual hosts. Hosts must be dual-stack hosts so they can tunnel IPv6 packets inside IPv4 packets. Teredo works through NAT. ISATAP and 6to4 tunneling both require at least one router. Because you only need to tunnel between two individual computers, Teredo is a more economical choice. Use 4to6 to tunnel IPv4 packets through an IPv6 network.
You manage a network with multiple subnets connected to the internet. A user reports that she can't access the internet. You investigate the problem and find that she can access all hosts on the private network, including subnets, but no hosts on the internet. Which of the following is likely the cause of the problem? Switching loop on the user's subnet Duplex mismatch between a switch and a router Missing default route on a router Incorrect default gateway setting on the computer
Missing default route on a router EXPLANATION If you can access all private subnets but not the internet, troubleshoot the connection to the internet. For example, verify that routers have a default route that would apply to internet traffic and make sure the internet link is up and working. The default gateway on the workstation is configured properly because routing to other subnets works correctly, meaning that the workstation is able to send and receive packets from remote networks. A duplex mismatch would cause slow communications, but some access might still be possible. A switching loop would affect devices within the subnet, not on other subnets.
You manage a network with multiple subnets connected to the internet. A user reports that she can't access the new server used in the accounting department. You check the problem and find out that her computer cannot access any server on that subnet. However, the computer does access other computers on other subnets as well as the internet. Which of the following is most likely the cause of the problem? Missing route on the default gateway router Incorrect VLAN membership of the accounting server Incorrect default gateway setting on the computer Switching loop on the user's subnet
Missing route on the default gateway router EXPLANATION The most likely cause of the problem is a missing route in one of the routers on your internal network (or that the router connecting that subnet to the network is down). Because the problem applies to all hosts in the remote subnet, you can suspect some type of misconfiguration of the router. The default gateway on the workstation is configured properly because routing to other subnets and the internet works correctly, meaning that the workstation is able to send and receive packets from remote networks. A switching loop would affect devices within the subnet, not on other subnets. Incorrect VLAN membership for the server would affect communications with the server only, not all devices on the subnet (unless all switch ports on the remote subnet are assigned to the same VLAN).
Which of the following functions are performed at the Physical layer of the OSI model? Conversation identification Provisioning environments where you can run network applications Data translation Enabling network services Moving data across network cables
Moving data across network cables EXPLANATION The Physical layer is concerned with how to transmit data and how to connect network hosts.
Which of the following address types is shared by multiple hosts and used to form groups of computers that receive the same data stream? Multicast Broadcast Unicast Half-duplex Simplex
Multicast EXPLANATION A multicast address is an address that identifies a group of computers. Members of the group share the same multicast address. A unicast address is an address that identifies a single host. A broadcast address is an address that is sent to all hosts. Broadcast traffic is typically only forwarded within (but not between) a subnet. Simplex communication uses a single channel for both sending and receiving. Half-duplex uses a separate channel for sending and receiving, but the channels are shared by multiple devices and can only be used by a single device at a time.
Which type of address is the IP address 232.111.255.250? Broadcast Multicast Unicast Private
Multicast EXPLANATION The address 232.111.255.250 is a multicast address. A multicast address is an address that identifies a group of computers. Members of the group share the same multicast address. Multicast addresses are in the range of 224.0.0.0 to 239.255.255.255. A unicast address is an address that identifies a single host. A broadcast address is an address that is sent to all hosts. Broadcast addresses are the last possible address on a subnet (typically ending in 255). The private IPv4 address ranges are: 10.0.0.1 to 10.255.255.254 172.16.0.1 to 172.31.255.254 192.168.0.1 to 192.168.255.254
Which address type is used for a video conference call consisting of multiple participants? Loopback Anycast Multicast Unicast
Multicast EXPLANATION Unified communication (UC) systems typically use unicast network transmissions. An example of a unicast transmission is a one-on-one VoIP phone call. UC systems also support multicast transmissions. Examples of a multicast transmission are conference phone calls or video conference calls consisting of multiple users.
Which type of switch optimizes network performance by using ASIC to perform switching at wire speed? Unmanaged switch Layer 2 switch Multilayer switch Layer 1 switch
Multilayer switch EXPLANATION A multilayer switch uses specialized hardware called an application-specific integrated circuit (ASIC) to perform switching functions in hardware rather than using the CPU and software. ASIC allows switches to perform the switching function at wire speed. Layer 2 switches use the CPU and software to forward frames. Unmanaged switches are also called Layer 2 switches. A Layer 1 switch is another name for a hub, which does not perform any traffic inspection; received packets are sent out on all ports.
You have a large TCP/IP network and want to keep a host's real time clock synchronized. What protocol should you use? NTP SAP SMTP SNMP NNTP
NTP EXPLANATION The network time protocol (NTP) lets you keep clocks synchronized.
At which OSI layer does a router operate to forward network messages? Physical Data Link Network Transport Session
Network EXPLANATION A router uses the logical network address specified at the Network layer to forward messages to the appropriate LAN segment. A bridge, on the other hand, uses the MAC address and works at the Data Link layer.
Which of the following devices operate at OSI model Layer 2? (Select two.) Firewall Repeater Network interface card Switch Hub Router
Network interface card Switch EXPLANATION A network interface card and a switch operate at Layer 2 (Data Link) of the OSI model. Layer 2 includes protocols that define the MAC address. The MAC address is burned into the network interface card, and a switch uses the MAC address to make forwarding decisions. A hub or a repeater operate at Layer 1; they regenerate a signal without looking at Layer 2 or Layer 3 information. A router operates at Layer 3, using the IP address to make forwarding decisions. A firewall operates at Layer 3 or higher, using packet or data contents to make filtering decisions.
Which of the following devices operate at the Data Link layer of the OSI model? (Select three.) Network interface cards (NICs) Switches Hubs Routers Bridges Repeaters
Network interface cards (NICs) Switches Bridges EXPLANATION Network interface cards (NICs), bridges, and switches all operate at the OSI Data Link layer. They use the physical device address (MAC address) to identify packets. Hubs and repeaters operate at the Physical layer--they simply repeat packets without regard to addresses. Routers function at the Network layer--they examine the logical device and network address to perform routing tasks.
Your company has a connection to the internet that allows users to access the internet. You also have a web server and an email server that you want to make available to internet users. You want to create a DMZ for these two servers. Which type of device should you use to create the DMZ? Host-based firewall IDS Network-based firewall IPS VPN concentrator
Network-based firewall EXPLANATION A demilitarized zone (DMZ) is a buffer network, or subnet, that sits between the private network and an untrusted network, such as the internet. To create a DMZ, use two network-based firewall devices, one connected to the public network, and one connected to the private network. A host-based firewall inspects traffic received by a host. Use a host-based firewall to protect your network from attacks when there is no network-based firewall, such as when you connect to the internet from a public location. A VPN concentrator is a device that is used to establish remote access VPN connections. An intrusion detection system (IDS) is a special network device that can detect attacks and suspicious activity. A passive IDS monitors, logs, and detects security breaches, but takes no action to stop or prevent attacks. An active IDS (also called an intrusion protection system, or IPS) performs the functions of an IDS, but can also react when security breaches occur.
You manage a small network at work. Users use workstations connected to your network. No portable computers are allowed. As part of your security plan, you would like to scan all users' emails. You want to scan the emails and prevent any e-mails with malicious attachments from being received by users. Your solution should minimize administration, allowing you to centrally manage the scan settings. Which solution should you use? Network-based firewall Host-based firewall DMZ SMTP
Network-based firewall EXPLANATION A network-based firewall inspects traffic as it flows between networks. For example, you can install a network-based firewall on the edge of your private network that connects to the internet and scans all incoming emails. Scanning emails as they arrive at your email server allows you to centralize management and stop malicious emails before they arrive at client computers. A demilitarized zone (DMZ), also called a screened subnet, is a buffer network, or subnet, that sits between the private network and an untrusted network, such as the internet. SMTP is an email protocol used by email servers for sending mail.
You have a network connected using a physical bus topology. One of the cables that connects a workstation to the bus breaks. Which of the following best describes what effect this will have on network communications? Devices on one side of the break will be able to communicate with each other; devices on the other side of the break will be able to communicate with each other. All devices will be able to communicate. All devices except the device connected with the drop cable will be able to communicate. Devices on one side of the break will be able to communicate with each other; devices on the other side will not be able to communicate. No devices will be able to communicate.
No devices will be able to communicate. EXPLANATION A break in the network bus means that the end of the network bus is no longer terminated. For this reason, a break in the bus typically means that no devices can communicate. Identifying the location of the break is difficult on a true bus network.
Which of the following routing protocols divides the network into areas, with all networks required to have an area 0 (area 0 identifying the backbone area)? RIP IS-IS OSPF EIGRP
OSPF EXPLANATION OSPF divides a large network into areas. Each autonomous system requires an area 0 that identifies the network backbone. All areas are connected to area 0, either directly or indirectly through another area. Routes between areas must pass through area 0. IS-IS uses areas, but does not have an area 0 requirement. Neither RIP nor EIGRP use areas.
Which of the following routing protocols uses relative link cost as the metric? BGP EIGRP OSPF RIP
OSPF EXPLANATION OSPF is a link-state routing protocol used for routing within an AS. OSPF uses relative link cost for the metric.
Which of the following best describes OSPF? OSPF is a classless distance vector routing protocol. OSPF is a classless link state routing protocol. OSPF is a classful link state routing protocol. OSPF is a classful distance vector routing protocol.
OSPF is a classless link state routing protocol. EXPLANATION OSPF is a classless link state routing protocol. RIP version 1 and IGRP are both classful distance vector routing protocols. EIGRP is a hybrid protocol that supports classless addressing.
What are the main differences between the OSPF and IS-IS routing protocols? OSPF is an IGP routing protocol, while IS-IS is a BGP routing protocol. OSPF is a link state protocol, while IS-IS is not. OSPF is a classful protocol, while IS-IS is a classless protocol. OSPF requires an area 0, while IS-IS does not.
OSPF requires an area 0, while IS-IS does not. EXPLANATION Like OSPF, IS-IS uses areas when designing the network. However, IS-IS does not require an area 0 like OSPF does. Because IS-IS was originally designed for non-IP protocols, it can more easily support IPv6 routing. Both OSPF and IS-IS have the following characteristics: Both are link state protocols. Both are classless protocols, supporting CIDR and VLSM. Both are Interior Gateway Protocols (IGPs) that are used within an AS.
You work for a large multinational organization that has an extensive global network that is interconnected using WAN links and routers. Lately, users in one location have complained that they are unable to access resources stored on a server named FS23 in a South American branch office. To troubleshoot the issue, you have done the following: Verified that the server is up and running. Verified that the various routers in between the two locations are up and running. You suspect that perhaps one of the routers between the two locations may be dropping packets. To test this theory, you enter the ping FS23 -f -l 1500 command on your workstation. The ping command returns the following command for each ping packet sent: "Packet needs to be fragmented but DF set." What does this mean? The destination host is down. Collisions are occurring on the network. One of the intermediate routers is an MTU black hole. Communications are functioning normally between your workstation and the target server. One of the intermediate routers is offline.
One of the intermediate routers is an MTU black hole. EXPLANATION A black hole router will drop packets when the packet size exceeds the maximum transmission unit (MTU) size. You can use ping to locate a black hole router by setting the following parameters along with the IP address of the remote host: -f causes the ping utility to send an ICMP echo packet that has the IP do not fragment bit set. -l sets the buffer (or payload) size of the ICMP echo packet. Specify this size by typing a number after the -l parameter. The ping test will provide you with helpful information: If the MTU of every segment of a routed connection is at least the MTU size, the ping is successful. If there is an intermediate segment that has a smaller MTU size, the router returns an ICMP destination unreachable packet, and the ping utility displays a "Packet needs to be fragmented but DF set" message.
After blocking a number of ports to secure your server, you are unable to send email. To allow email service, which of the following needs to be done? Open port 80 to allow SNMP service. Open port 110 to allow SMTP service. Open port 80 to allow SMTP service. Open port 25 to allow SMTP service. Open port 25 to allow SNMP service. Open port 110 to allow POP3 service.
Open port 25 to allow SMTP service. EXPLANATION The simple mail transfer protocol (SMTP) uses TCP port 25 and is responsible for sending email. If port 25 is blocked, users will not be able to send email, but they could receive email using port 110 and the POP3 protocol. SNMP is used to monitor network traffic. POP3 uses port 110 and is used to retrieve email from a mail server.
Match the firewall type on the left with its associated characteristics on the right. Each firewall type may be used once, more than once, or not at all. Drag: Routed firewall Virtual firewall Drop: Operates at Layer 2. Operates at Layer 3. Counts as a hop in the path between hosts. Does not count as a hop in the path between hosts. Each interface connects to a different network. Each interface connects to the same network segment.
Operates at Layer 2. - Virtual firewall Operates at Layer 3. - Routed firewall Counts as a hop in the path between hosts. - Routed firewall Does not count as a hop in the path between hosts. - Virtual firewall Each interface connects to a different network. - Routed firewall Each interface connects to the same network segment. - Virtual firewall EXPLANATION In a routed firewall, the firewall is also a Layer 3 router. In fact, many hardware routers include firewall functionality. Transmitting data through this type of firewall counts as a router hop. A routed firewall usually supports multiple interfaces, each connected to a different network segment. A transparent firewall (also called a virtual firewall) works differently. It operates at Layer 2, and it is not seen as a router hop by connected devices. Both the internal and external interfaces on a transparent firewall connect to the same network segment. Because it is not a router, you can easily introduce a transparent firewall into an existing network.
Which of the following are true of a circuit proxy filter firewall? (Select two.) Operates at ring 0 of the operating system. Operates at the Network and Transport layers. Examines the entire message contents. Operates at the Session layer. Verifies sequencing of session packets. Operates at the Application layer.
Operates at the Session layer. Verifies sequencing of session packets. EXPLANATION A circuit proxy filter firewall operates at the Session layer. It verifies the sequencing of session packets, breaks the connections, and acts as a proxy between the server and the client. An Application layer firewall operates at the Application layer, examines the entire message, and can act as a proxy to clients. A stateful inspection firewall operates at the Network and Transport layers. It filters on both IP addresses and port numbers. A kernel proxy filtering firewall operates at the operating system ring 0.
Which of the following associates a port number with a host on a private network? VLSM CIDR PAT NAT
PAT EXPLANATION Port address translation (PAT) associates a port number with the translated address. Use PAT to allow multiple private hosts to share a single public address. Each private host is associated with a unique port number. Technically speaking, NAT translates one address to another. With only NAT, you would have to have a public address for each private host. NAT would associate a single public address with a single private address. Because virtually all NAT routers perform port address translation, most routers that are configured with NAT are really performing PAT. When you use a NAT router, you normally use PAT, not just NAT. (NAT is typically used synonymously with PAT.) Classless inter-domain routing (CIDR) allows non-default subnet masks (variable-length subnet masks, or VLSMs).
Which of the following TCP/IP protocols do email clients use to download messages from a remote mail server? SMTP POP3 SPC FTP SNMP
POP3 EXPLANATION The POP3 protocol is part of the TCP/IP protocol suite. It is used to retrieve email from a remote server to a local client over a TCP/IP connection. SNMP is a protocol used to monitor network traffic. SMTP is a TCP/IP protocol used to send email. FTP is used to transfer files.
Which of the following best describes the platform as a service (PaaS) cloud computing service model? PaaS delivers software applications to the client either over the internet or on a local area network. PaaS delivers infrastructure to the client, such as processing, storage, networks, and virtualized environments. PaaS delivers everything a developer needs to build an application onto the cloud infrastructure. PaaS stores and provides data from a centralized location without requiring local collection and storage.
PaaS delivers everything a developer needs to build an application onto the cloud infrastructure. EXPLANATION Platform as a service (PaaS) delivers everything a developer needs to build an application on the cloud infrastructure. The deployment comes without the cost and complexity of buying and managing the underlying hardware and software layers. Software as a service (SaaS) delivers software applications to the client either over the internet or on a local area network. Infrastructure as a service (IaaS) delivers infrastructure to the client, such as processing, storage, networks, and virtualized environments. The client deploys and runs software without purchasing servers, data center space, or network equipment. Data as a service (DaaS) stores and provides data from a centralized location without requiring local collection and storage.
Which of the following is a firewall function? FTP hosting Packet filtering Protocol conversion Encrypting Frame filtering
Packet filtering EXPLANATION Firewalls often filter packets by checking each packet against a set of administrator-defined criteria. If the packet is not accepted, it is simply dropped.
Which of the following is a firewall function? Protocol conversion Encrypting Packet filtering FTP hosting Frame filtering
Packet filtering EXPLANATION Firewalls often filter packets by checking each packet against a set of administrator-defined criteria. If the packet is not accepted, it is simply dropped.
Match the firewall type on the right with the OSI layer at which it operates. Each OSI Layer may be used once, more than once, or not at all. Drag: OSI Layer 1 OSI Layer 2 OSI Layer 3 OSI Layer 4 OSI Layer 5 OSI Layer 6 OSI Layer 7 Drop: Packet filtering firewall Circuit-level proxy Application-level gateway Routed firewall Transparent firewall
Packet filtering firewall - OSI Layer 3 Circuit-level proxy - OSI Layer 5 Application-level gateway - OSI Layer 7 Routed firewall - OSI Layer 3 Transparent firewall - OSI Layer 2 EXPLANATION Each firewall type operate at a specific layer of the OSI model. Packet filtering firewalls operate at Layer 3. Circuit-level proxies operate at Layer 5. Application-level gateways operate at Layer 7. Routed firewalls operate at Layer 3. Transparent firewalls operate at Layer 2.
Your manager has asked you to implement a wired network infrastructure that will accommodate failed connections. You don't have a large budget, so you decide to provide redundancy for only a handful of critical devices. Which of the following network topologies should you implement? Full mesh Bus Star Partial mesh
Partial mesh EXPLANATION In a partial mesh topology, only some redundant paths exist. A partial mesh topology is more practical and less expensive than a full mesh topology. In a full mesh topology, every device has a point-to-point connection with every other device. This provides full redundancy, but it is expensive and impractical. A star topology connects network devices to the network with a single patch cable; a patch cable failure makes the connected device unavailable. A bus topology has a single point of failure. If there is a break in the network media, the network becomes unavailable.
You have implemented a network where each device provides all other devices on the network with access to shared files. What type of network do you have? Polling Client-server Multiple access Peer-to-peer
Peer-to-peer EXPLANATION In a peer-to-peer network, each host can provide network resources to other hosts or access resources located on other hosts, and each host is in charge of controlling access to those resources. In a client/server network, hosts have specific roles. For example, some hosts are assigned server roles, which allow them to provide network resources to other hosts. Other hosts are assigned client roles, which allow them to consume network resources. Polling is a media access method where a single device grants permission to other devices to access the network. Multiple access describes a media access method where each device determines when the medium is free.
At which layer of the OSI model do hubs operate? Layer 3 Data Link Physical Internet
Physical EXPLANATION Hubs operate at Layer 1, or the Physical layer of the OSI model.
Which of the following features is used with digital IP phones to supply power through a switch port? Trunking VPN Spanning tree PoE 802.1x
PoE EXPLANATION Power over Ethernet (PoE) supplies power to end devices through the RJ45 Ethernet switch port. Power to the phone is carried on unused wires within the drop cables. Spanning tree is a protocol on a switch that allows the switch to maintain multiple paths between switches within a subnet. The spanning tree protocol runs on each switch and is used to select a single path between any two switches. Trunking allows a switch to forward VLAN traffic between switches. 802.1x is an authentication protocol used with port security or port authentication.
Listed below are several DNS record types. Match the record type on the left with its function on the right. Drag: A CNAME MX PTR AAAA Drop: Points a host name to an IPv4 address. Provides alternate names to hosts that already have a host record. Points an IP address to a host name. Points a hostname to an IPv6 address. Identifies servers that can be used to deliver mail.
Points a host name to an IPv4 address. - A Provides alternate names to hosts that already have a host record. - CNAME Points an IP address to a host name. - PTR Points a hostname to an IPv6 address. - AAAA Identifies servers that can be used to deliver mail. - MX EXPLANATION Records are used to store entries for host names, IP addresses, and other information in the zone database. Below are some common DNS record types: The A record maps an IPv4 (32-bit) DNS host name to an IP address. This is the most common resource record type. The AAAA record maps an IPv6 (128-bit) DNS host name to an IP address. The PTR record maps an IP address to a host name (in a manner of speaking, it points to an A record). The MX record identifies servers that can be used to deliver email. The CNAME record provides alternate names (or aliases) to hosts that already have a host record. Using a single A record with multiple CNAME records means that when the IP address changes, only the A record needs to be modified.
Which of the following techniques allows incoming traffic addressed to a specific port to move through a NAT router and be forwarded to a specific host? Port address translation EIGRP Port forwarding Spanning tree protocol
Port forwarding EXPLANATION Port forwarding is a type of static NAT implementation where a specific port is mapped to a private IP address. Incoming traffic that is addressed to a specific port is then forwarded to the specified host. Port address translation (PAT) is used to keep track of which request goes to which host on the internal network. EIGRP is a routing protocol used to exchange information about known routes with other routers. The spanning tree protocol is used to eliminate switching loops within a network.
You have just installed a packet filtering firewall on your network. Which options will you be able to set on your firewall? (Select all that apply.) Sequence number Port number Acknowledgement number Checksum Digital signature Source address of a packet Destination address of a packet
Port number Source address of a packet Destination address of a packet EXPLANATION Firewalls allow you to filter by IP address and port number.
You have just installed a packet filtering firewall on your network. Which options will you be able to set on your firewall? (Select all that apply.) Port number Source address of a packet Checksum Acknowledgement number Digital signature Sequence number Destination address of a packet
Port number Source address of a packet Destination address of a packet EXPLANATION Firewalls allow you to filter by IP address and port number.
Match each layer of the TCP/IP model on the left with the corresponding layer of the OSI model on the right. Each option on the left can be used more than once. Drag: Host-to-Host Internet Network Access Application Drop: Presentation Data Link Application Session Network Transport
Presentation - Application Data Link - Network Access Application - Application Session - Application Network - Internet Transport - Host-to-Host EXPLANATION The TCP/IP networking model maps to the OSI networking model as follows: Application - Application/ Presentation/ Session Host-to-Host Transport - Transport Internet - Network Network Access -Data Link (Hardware) - Physical
You have a small network at home that is connected to the internet. On your home network, you have a server with the IP address of 192.168.55.199/16. All computers on your home network can connect to the internet. From your work office, you try to access your home computer using its IP address, but are unable to communicate with the server. You are able to connect to other hosts on the internet. Why can't you access the server? The server isn't using the default subnet mask. Private addresses are not accessible through the internet. The server has been assigned a multicast address. The server must have an entry on a DNS server that exists on the internet.
Private addresses are not accessible through the internet. EXPLANATION The server has been assigned a private IP address. Private addresses are not accessible from the internet. Instead, a NAT router translates the private address into a public address, and the public address is used to gain access to the private host.
CorpServ is a small company with 14 client systems and a network printer. Because there are only a limited number of networked systems, you decide to use APIPA addressing for the network. With APIPA configured, all systems are able to communicate with each other, but you are having trouble configuring Internet access. What is the likely cause of the problem? The default gateway is not set on the server. The DNS server is unavailable to resolve internet host names. All client systems must be rebooted. The default gateway is not set on the client systems. Private addresses cannot directly communicate to hosts outside the local subnet.
Private addresses cannot directly communicate to hosts outside the local subnet. EXPLANATION APIPA assigns private addresses designed for use on single-subnet networks that do not use routers. If internet access is required, APIPA cannot be used to provide clients direct access to the internet. APIPA is enabled by default and will assign an address if the DHCP server is unavailable. APIPA assigns only an IP address and subnet mask. A default gateway and DNS servers are not required to access network resources.
What is the purpose of using Ethernet bonding? (Select two.) Provides increased bus speeds. Increases read and write operations between the system bus and network adapters. Provides a failover solution for network adapters. Increases network performance. Enables Dual Remote Access (DRA) over a WAN link.
Provides a failover solution for network adapters. Increases network performance. EXPLANATION In a true fault tolerant strategy, all system components must be considered. Ethernet bonding (also called adapter teaming) is a fault tolerant strategy that uses multiple network adapters configured in a failover solution. In the event of a NIC failure, other adapters will automatically provide link redundancy. Multiple adapters can also increase performance by distributing the network load between adapters.
Which of the following solutions would you implement to track which websites network users are accessing? Tarpit NIDS Proxy Packet filtering firewall
Proxy EXPLANATION A proxy server is a device that stands as an intermediary between a secure private network and the public. It is a specific implementation of an Application layer firewall. A proxy stops and inspects every packet at the firewall, which causes a break between the client and the source server. Proxies can be configured to filter content, monitor internet access, or restrict access by user or by website. A packet filtering firewall examines the packet header information to make forwarding decisions. The firewall can accept or reject packets based on IP address, but not individual websites. A network-based IDS (NIDS) is a dedicated device installed on the network. It analyzes all traffic on the network to look for potential attacks. A tarpit (also called a sticky honeypot) is a honeypot that answers connection requests in such a way that the attacking computer is stuck for a period of time.
You manage a server that runs your company website. The web server has reached its capacity, and the number of client requests is greater than the server can handle. You would like to find a solution so that static web content can be offloaded to a different server while the web server continues to process dynamic content. Which solution should you implement? QoS Proxy server Traffic shaper Ethernet bonding
Proxy server EXPLANATION A common application of a caching engine on a network is a proxy server configured to cache web content. As users visit websites, web content is retrieved from the web server and cached on the proxy server. Subsequent requests for the same content are handled by the proxy server from cache rather than retrieved from the web server. A traffic shaper (also called a bandwidth shaper) is a device that is capable of modifying the flow of data through a network in response to network traffic conditions. Quality of Service (QoS) refers to a set of mechanisms that try to guarantee timely delivery or minimal delay of important or time-sensitive communications. QoS is particularly important if you implement Voice over IP (VoIP), Video over IP, or online games where delay or data loss make the overall experience unacceptable. Ethernet bonding (also called NIC teaming), logically groups two or more physical connections to the same network. Data is divided and sent on multiple interfaces, effectively increasing the speed at which the device can send and receive on the network.
Match each description on the left with the appropriate cloud technology on the right. Drag: Provides cloud services to just about anyone. Allows cloud services to be shared by several organizations. Integrates one cloud service with other cloud services. Provides cloud services to a single organization. Drop: Public cloud Private cloud Community cloud Hybrid cloud
Public cloud - Provides cloud services to just about anyone. Private cloud - Provides cloud services to a single organization. Community cloud - Allows cloud services to be shared by several organizations. Hybrid cloud - Integrates one cloud service with other cloud services. EXPLANATION Cloud computing can be implemented in several different ways, including the following: A public cloud can be accessed by anyone. Cloud-based computing resources are made available to the general public by a cloud service provider. The service provider may or may not require a fee for using these resources. For example, Google provides many publicly accessible cloud applications, such as Gmail and Google Docs. A private cloud provides resources to a single organization. Access is restricted to only the users within that organization. An organization commonly enters into an agreement with a cloud service provider that provides secure access to cloud-based resources. The organization's data is kept separate and secure from any other organization using the same service provider. A community cloud is designed to be shared by several organizations. Access is restricted to only users within the organizations who are sharing the community cloud infrastructure. Community clouds are commonly hosted externally by a third party. A hybrid cloud is composed of a combination of public, private, and community cloud resources from different service providers. The goal behind a hybrid cloud is to expand the functionality of a given cloud service by integrating it with other cloud services.
Your computer has an IP address of 161.13.5.15. Your computer is on a: Class C network Private network Public network Multi-cast network
Public network EXPLANATION Most IP addresses are public IP addresses. However, certain ranges have been reserved for private networks. These are: 10.0.0.0 - 10.255.255.255 172.16.0.0 - 172.31.255.255 192.168.0.0 - 192.168.255.255 Because your computer's IP address does not fall into these ranges, it is a public IP address.
You have used firewalls to create a demilitarized zone. You have a web server that needs to be accessible to internet users. The web server must communicate with a database server for retrieving product, customer, and order information. How should you place devices on the network to best protect the servers? (Select two.) Put the database server inside the DMZ. Put the web server on the private network. Put the database server on the private network. Put the web server inside the DMZ.
Put the database server on the private network. Put the web server inside the DMZ. EXPLANATION Publicly accessible resources (servers) are placed inside the DMZ. Examples of publicly accessible resources include web, FTP, and email servers. Devices that should not be accessible to public users are placed on the private network. If you have a public server that communicates with another server, such as a database server, and that server should not have direct contact with public hosts, place the server on the private network and allow only traffic from the public server to cross the inner firewall.
Which of the following protocols has a limit of 15 hops between any two networks? OSPF EIGRP RIP BGP IS-IS
RIP EXPLANATION RIP networks are limited in size to a maximum of 15 hops between any two networks. A network with a hop count of 16 indicates an unreachable network. The other routing protocols do not use the hop count as the metric. EIGRP uses bandwidth and delay for the metric. OSPF and IS-IS use a relative link cost. BGP uses paths, rules, and policies for the metric.
What is the main difference between RIP and RIPv2? RIP is a classful protocol, while RIPv2 is a classless protocol. RIP is a distance vector protocol, while RIPv2 is a link state protocol. RIP has a limit of 15 hops, while RIPv2 increases the hop count limit. RIP use the hop count for the metric, while RIPv2 uses a relative link cost.
RIP is a classful protocol, while RIPv2 is a classless protocol. EXPLANATION RIP v1 is a classful protocol, meaning that the subnet mask is not included in routing updates. With RIP, only the default subnet mask is used to identify networks. RIP v2 is a classless protocol, meaning that the subnet mask is included in routing updates. RIPv2 supports variable length subnet masks (VLSM). Both RIP and RIPv1 are distance vector protocols and use the hop count for the metric. RIP and RIPv2 have a limit of 15 hops between any two networks.
Which of the following statements about RIP is true? RIP uses hop counts as the cost metric. RIP is a link state routing protocol. RIP is the routing protocol used on the internet. RIP is suitable for large networks.
RIP uses hop counts as the cost metric. EXPLANATION RIP is a distance vector routing protocol. As such, it is susceptible to the count-to-infinity problem. RIP uses the hop count as the cost metric. Because it has a limitation of 15 hops in one route, it is not suited for large networks.
You need to configure spanning tree on a Cisco switch. You'd like to use a protocol that conforms to the 802.1w standards. Which protocol should you use? PortFast BPDU guard EtherChannel Rapid PVST+
Rapid PVST+ EXPLANATION Rapid PVST+ is the IEEE 802.1w standard. RSTP improves convergence by actively confirming that a switch is ready to transition to a forwarding state, eliminating the listening and learning stages. RSTP defines several new types of links and uses fewer spanning tree states. PortFast allows a port connected to a host to go into a forwarding state almost immediately. PortFast ports must be used only for connections to end user devices, such as workstations or server systems. PortFast should not be used when the port is connected to a bridge, a switch, or another STP speaking device. EtherChannel combines multiple parallel physical links into a single logical channel. The switch treats the logical channel as a single interface that provides redundancy, as well as load sharing among the links in the channel. BPDU guard is frequently used with PortFast to ensure the stability of the STP topology. BPDU guard disables a port configured by PortFast if that port receives BPDUs.
Based on the diagram, which type of proxy server is handling the client's request? Reverse proxy server Circuit-level proxy server Forward proxy server Open proxy server
Reverse proxy server EXPLANATION A reverse proxy server handles requests from the internet to an internal network. Instead of requests for a server going directly to the server, they first go to the reverse proxy server. A forward proxy server handles requests from an internal network out to the internet. An open proxy server is accessible to any user on the internet and is used to forward requests to and from anywhere on the internet. A circuit-level proxy server is typically used as a stateful firewall to allow or deny sessions.
Which of the following topologies connects each device to a neighboring device? Bus Tree Star Ring
Ring EXPLANATION In ring topologies, each device connects to a neighboring device so that a ring is formed.
In which of the following topologies does each device on the network act as a repeater, sending the signal to the next device? Ring Star Bus Tree
Ring EXPLANATION In ring topologies, each device on the network acts as a repeater for sending the signal to the next device.
Which of the following tasks do routers perform? (Select two.) Route data based on logical network addresses. Control access to the transmission media. Multiplex signals onto the same transmission media. Maintain information about paths through an internetwork. Route data based on hardware device addresses. Identify devices through hardware addresses.
Route data based on logical network addresses. Maintain information about paths through an internetwork. EXPLANATION Routers build and maintain tables of routes through an internetwork and deliver data between networks based on logical network addresses.
In the OSI model, what is the primary function of the Network layer? Transmits data frames Routes messages between networks Ensures that packets are delivered with no loss or duplication Allows applications to establish, use, and end a connection
Routes messages between networks EXPLANATION The Network layer is responsible for routing messages between networks.
You manage a network with two switches. The switches are connected together through their Gigabit Ethernet uplink ports. You define VLAN 1 and VLAN 2 on each switch. A device on the first switch in VLAN 1 needs to communicate with a device on the same switch which is in VLAN 2. What should you configure so that the two devices can communicate? Trunking Mirroring Routing Spanning tree PoE
Routing EXPLANATION In a typical configuration with multiple VLANs and a single or multiple switches, workstations in one VLAN will not be able to communicate with workstations in other VLANs. To enable inter-VLAN communication, you will need to use a router (or a Layer 3 switch). Trunking is used to configure switch ports to carry VLAN traffic between switches or between a router and a switch. If you configured a single router to connect to the switch with a single physical interface, you would have to configure trunking on that interface in addition to routing. Trunking by itself would not enable the two devices to communicate. Spanning tree is a protocol on a switch that allows the switch to maintain multiple paths between switches within a subnet. The spanning tree protocol runs on each switch and is used to select a single path between any two switches. Mirroring sends traffic from all switch ports to a switch port you designate as the mirrored port. Power over Ethernet (PoE) supplies power to end devices through the RJ45 Ethernet switch port.
You have a Windows Server 2016 system that you want to use as a DHCP relay agent. Which Windows Server 2016 service would you use to do this? DNS Routing and Remote Access Network Policy Server Internet Information Services (IIS) Manager
Routing and Remote Access EXPLANATION In Windows Server 2016, the DHCP Relay Agent role is enabled and configured using the Routing and Remote Access service. Before a Windows server can be used as a DHCP Relay Agent, the Routing and Remote Access service (RRAS) must be installed.
What protocol sends email to a mail server? SNMP POP3 SMTP FTP TFTP
SMTP EXPLANATION SMTP sends email to a mail server.
Your company has just acquired another company in the same city. You need to integrate the two email systems so that messages can be exchanged between the email servers. Currently, each network uses an email package from a different vendor. Which TCP/IP protocol will enable message exchange between systems? SMTP POP3 IMAP4 ICMP FTP
SMTP EXPLANATION The simple mail transfer protocol (SMTP) specifies how messages are exchanged between email servers. Email clients use POP3 and IMAP4 to download email messages from email servers. FTP is a file transfer protocol. ICMP is used in ping and traceroute to communicate network information.
Which of the following network services or protocols uses TCP/IP port 22? SSH TFTP NNTP IMAP4
SSH EXPLANATION The Secure Shell (SSH) service uses TCP/IP port 22. SSH is a terminal emulation program similar to Telnet, which provides secure authenticated sessions on a remote system. It is most commonly associated with Unix and Linux systems. The trivial file transfer protocol (TFTP) is a connectionless service for downloading files from a remote system. TFTP uses TCP/IP port 69. The network news transfer protocol (NNTP) is used to access and download messages from newsgroup servers. NNTP uses TCP/IP port 119. The internet message access protocol version 4 (IMAP4) is used to download email from remote servers. IMAP 4 uses TCP/IP port 143.
Which of the following cloud computing solutions will deliver software applications to a client either over the internet or on a local area network? DaaS SaaS PaaS IaaS
SaaS EXPLANATION Software as a service (SaaS) delivers software applications to the client either over the internet or on a local area network. Infrastructure as a service (IaaS) delivers infrastructure to the client, such as processing, storage, networks, and virtualized environments. The client deploys and runs software without purchasing servers, data center space, or network equipment. Platform as a service (PaaS) delivers everything a developer needs to build an application onto the cloud infrastructure. The deployment comes without the cost and complexity of buying and managing the underlying hardware and software layers. Data as a service (DaaS) stores and provides data from a centralized location without requiring local collection and storage.
A switch receives a frame addressed to the MAC address FF:FF:FF:FF:FF:FF. What will the switch do with the frame? Process the frame and respond to the sending device. Forward it out the port and to the device with that MAC address. Drop the frame. Send it out all ports except for the port it was received on.
Send it out all ports except for the port it was received on. EXPLANATION The MAC address FF:FF:FF:FF:FF:FF identifies the broadcast address, meaning all hosts on the subnet. Switches forward broadcast frames out all ports except for the port on which the frame was received.
During TCP/IP communications between two network hosts, information is encapsulated on the sending host and decapsulated on the receiving host using the OSI model. Match the information format on the left with the appropriate layer of the OSI model on the right. (Not all layers have a matching information format.) Drag: Packets Segments Bits Frames Drop: Session Layer Transport Layer Network Layer Data Link Layer Physical Layer
Session Layer - blank Transport Layer - Segments Network Layer - Packets Data Link Layer - Frames Physical Layer - Bits EXPLANATION Encapsulation is the process of breaking a message into packets, adding control and other information, and transmitting the message through the transmission media. The following is the five-step data encapsulation/decapsulation process used by the OSI model: Upper layers prepare the data to be sent through the network. The Transport layer breaks the data into pieces called segments, adding sequencing and control information. The Network layer converts the segments into packets, adding logical network and device addresses. The Data Link layer converts the packets into frames, adding physical device addressing information. The Physical layer converts the frames into bits for transmission across the transmission media.
You are monitoring network traffic on your network, and you see traffic between two network hosts on port 1720. What is the source of this network traffic? Someone is using voice over IP (VoIP) to make a telephone call. Someone is downloading files from a server using the FTP protocol. A workstation is using the DNS protocol to send a name resolution request to a DNS server. A man-in-the-middle attack is in progress.
Someone is using voice over IP (VoIP) to make a telephone call. EXPLANATION Someone on the network is using voice over IP (VoIP) to make a telephone call. Some VoIP implementations use the H.323 protocol to set up, maintain, tear down, and redirect calls. H.323 uses port 1720. The DNS protocol sends name resolution requests to a DNS server on port 53. In a man-in-the-middle attack, a legitimate communication session between two network hosts is intercepted and possibly modified by an attacker. The FTP protocol uses ports 20 and 21 to transfer files between two network hosts.
Which of the following solutions would you implement to eliminate switching loops? CSMA/CD Inter-VLAN routing Auto-duplex Spanning tree
Spanning tree EXPLANATION Run the spanning tree protocol to prevent switching loops. A switching loop occurs when there are multiple active paths between switches. The spanning tree protocol runs on each switch and is used to select a single path between any two switches. Switch ports that are part of that path are placed in a forwarding state. Switch ports that are part of redundant but unused paths are placed in a blocking (non-forwarding) state. Use inter-VLAN routing to enable devices in different VLANs to communicate. The auto-duplex setting allows a switch port to detect the duplex setting of connected devices (either half- or full-duplex). CSMA/CD is a method for detecting and recovering from collisions.
You manage a single subnet with three switches. The switches are connected to provide redundant paths between the switches. Which feature prevents switching loops and ensures there is only a single active path between any two switches? Spanning tree PoE Trunking 802.1x Bonding
Spanning tree EXPLANATION Spanning tree is a protocol on a switch that allows the switch to maintain multiple paths between switches within a subnet. The spanning tree protocol runs on each switch and is used to select a single path between any two switches. Without the spanning tree protocol, switches that are connected with multiple links would form a switching loop, where frames are passed back and forth continuously. Spanning tree provides only a single active path between switches. Switch ports that are part of that path are placed in a forwarding state. Switch ports that are part of redundant but unused paths are placed in a blocking (non-forwarding) state. When an active path goes down, the spanning tree protocol automatically recovers and activates the backup ports necessary to provide continued connection between devices. Bonding performs spanning tree's opposite function--it allows multiple switch ports to be used at the same time to reach a specific destination. 802.1x is an authentication protocol used with port security (or port authentication). Power over Ethernet (PoE) supplies power to end devices through the RJ45 Ethernet switch port. Trunking identifies ports that are used to carry VLAN traffic between switches. A trunk port is a member of all VLANs defined on all switches.
Which of the following features dynamically places switch ports in blocking or forwarding states? Mirroring Spanning tree Trunking PoE
Spanning tree EXPLANATION Spanning tree is a protocol on a switch that allows the switch to maintain multiple paths between switches within a subnet. The spanning tree protocol runs on each switch and is used to select a single path between any two switches. Without the spanning tree protocol, switches that are connected with multiple links would form a switching loop, where frames are passed back and forth continuously. Spanning tree provides only a single active path between switches. Switch ports that are part of that path are placed in a forwarding state. Switch ports that are part of redundant but unused paths are placed in a blocking (non-forwarding) state. When an active path goes down, the spanning tree protocol automatically recovers and activates the backup ports necessary to provide continued connection between devices. Trunking identifies ports that are used to carry VLAN traffic between switches. A trunk port is a member of all VLANs defined on all switches. Mirroring sends traffic from all switch ports to a switch port you designate as the mirrored port. Power over Ethernet (PoE) supplies power to end devices through the RJ45 Ethernet switch port.
You manage a network that uses multiple switches. You want to provide multiple paths between switches so that if one link goes down, an alternate path is available. Which feature should your switch support? PoE OSPF Spanning tree Trunking Mirroring
Spanning tree EXPLANATION Spanning tree is a protocol on a switch that allows the switch to maintain multiple paths between switches within a subnet. The spanning tree protocol runs on each switch and is used to select a single path between any two switches. Without the spanning tree protocol, switches that are connected with multiple links would form a switching loop, where frames are passed back and forth continuously. Spanning tree provides only a single active path between switches. Switch ports that are part of that path are placed in a forwarding state. Switch ports that are part of redundant but unused paths are placed in a blocking (non-forwarding) state. When an active path goes down, the spanning tree protocol automatically recovers and activates the backup ports necessary to provide continued connection between devices. Trunking identifies ports that are used to carry VLAN traffic between switches. A trunk port is a member of all VLANs defined on all switches. Mirroring sends traffic from all switch ports to a switch port you designate as the mirrored port. Power over Ethernet (PoE) supplies power to end devices through the RJ45 Ethernet switch port. OSPF is a routing protocol that routers use to learn about and select routes to destination networks.
You are configuring the DHCP Relay Agent role on a Windows server. Which of the following is a required step for the configuration? Specify which server network interface the agent listens on for DHCP messages. Connect an RFC 1542 compliant router to the Windows server. Use the ip helper-address command to specify the remote DHCP server. Configure the Windows server to be on the same subnet as the DHCP server.
Specify which server network interface the agent listens on for DHCP messages. EXPLANATION When configuring the DHCP Relay Agent role, you need to specify which server network interface the agent will listen on for DHCP messages. The ip helper-address command is used to configure DHCP relay on Cisco routers, not Windows servers. An RFC 1542-compliant router is not necessary for DHCP relay when using the Windows Server DHCP Relay Agent. Configuring the Windows server to be on the same subnet as the DHCP server would prevent the server from being able to relay DHCP messages from a different subnet.
You have a small network that uses a switch to connect multiple devices. Which physical topology are you using? Star Bus Mesh Ring
Star EXPLANATION A hub creates a network with a physical star topology. The physical star topology uses a logical bus topology and sends messages to all the devices connected to the hub. A mesh topology is a series of point-to-point links between devices. A ring topology uses a central device called an MSAU.
Which of the following topologies connects each network device to a central hub? Star Ring Mesh Bus
Star EXPLANATION Star topologies connect each device on the network to a central hub.
Which of the following physical topologies are used with Ethernet networks? (Select two.) Star Mesh Ring Bus
Star Bus EXPLANATION Ethernet networks use either a physical bus or physical star topology. Hubs can also be cascaded to form a tree topology.
Which of the following are characteristics of a packet filtering firewall? (Select two.) Stateless Stateful Filters by URL Filters IP addresses, not ports Filters by session
Stateless Filters IP addresses, not ports EXPLANATION A packet filtering firewall makes decisions about which network traffic to allow by examining information in the IP packet header, such as source and destination addresses, ports, and service protocols. A packet filtering firewall is considered a stateless firewall because it examines each packet and uses rules to accept or reject each packet without considering whether the packet is part of a valid and active session.
You manage a network that uses IPv6 addressing. When clients connect devices to the network, they generate an interface ID and use NDP to learn the subnet prefix and default gateway. Which IPv6 address assignment method is being used? Static partial assignment Stateful DHCPv6 Stateless autoconfiguration Static full assignment
Stateless autoconfiguration EXPLANATION With stateless autoconfiguration, clients automatically generate an interface ID and learn the subnet prefix and default gateway through the neighbor discovery protocol (NDP). With static full assignment, the entire 128-bit address and all other configuration information is statically assigned. Static partial assignment generates the interface ID from the MAC address, and clients are statically assigned the prefix. Stateful DHCPv6 is when the DHCP server provides each client with an IP address, default gateway, and other IP configuration information.
You are the network administrator for a small company that implements NAT to access the internet. You recently acquired five servers that must be accessible from outside your network. Your ISP has provided you with five additional registered IP addresses to support these new servers, but you don't want the public to access these servers directly. You want to place these servers behind your firewall on the inside network, yet still allow them to be accessible to the public from the outside. Which method of NAT translation should you implement for these five servers? Dynamic Restricted Static Overloading
Static EXPLANATION Static translation consistently maps an unregistered IP address to the same registered IP address on a one-to-one basis. Static NAT is particularly useful when a device needs to be assigned the same address so it can be accessed from outside the network, such as web servers and other similar devices. Dynamic translation would not work for these servers because it maps an unregistered host IP address to any available IP address configured in a pool of one or more registered IP addresses. Accessing a server assigned one of these addresses would be nearly impossible because the addresses are still shared by multiple hosts.
Match the IPv6 address configuration method on the right with its definition on the left. Drag: Clients automatically generate the interface ID and learn the subnet prefix and default gateway through the neighbor discovery protocol (NDP). Provides each client with an IP address, default gateway, and other IP configuration information. The prefix is statically assigned, and the interface ID is derived from the MAC address. The entire 128-bit address and all other configuration information is statically assigned to the host. Supplies the client with the DNS server IP address only. Does not provide the client with an IP address, and does not track the status of each client. Drop: Static Full Assignment Static Partial Assignment Stateless Autoconfiguration Stateful DHCPv6 Stateless DHCPv6
Static Full Assignment - The entire 128-bit address and all other configuration information is statically assigned to the host. Static Partial Assignment - The prefix is statically assigned, and the interface ID is derived from the MAC address. Stateless Autoconfiguration - Clients automatically generate the interface ID and learn the subnet prefix and default gateway through the neighbor discovery protocol (NDP). Stateful DHCPv6 - Provides each client with an IP address, default gateway, and other IP configuration information. Stateless DHCPv6 - Supplies the client with the DNS server IP address only. Does not provide the client with an IP address, and does not track the status of each client. EXPLANATION An IPv6 address can be configured using any of the following methods: Static Full Assignment: The entire 128-bit address and all other configuration information is statically assigned to the host. Static Partial Assignment: The prefix is statically assigned, and the interface ID is derived from the MAC address. Stateless Autoconfiguration: Clients automatically generate the interface ID and learn the subnet prefix and default gateway through the neighbor discovery protocol (NDP). Stateful DHCPv6: Provides each client an IP address, default gateway, and other IP configuration information. Stateless DHCPv6: Supplies the client with the DNS server IP address only. Does not provide the client an IP address, and does not track the status of each client.
You have a small network at home that is connected to the internet. On your home network, you have a server with the IP address of 192.168.55.199/16. You have a single public address that is shared by all hosts on your private network. You want to configure the server as a web server and allow internet hosts to contact the server to browse a personal website. What should you use to allow access? DNS CNAME record Multicast Static NAT DNS A record Dynamic NAT
Static NAT EXPLANATION Static NAT maps an internal IP address to a static port assignment. Static NAT is typically used to take a server on the private network (such as a web server) and make it available on the internet. External hosts contact the internal server using the public IP address and the static port. Using a static mapping allows external hosts to contact internal hosts. Dynamic NAT automatically maps internal IP addresses with a dynamic port assignment. On the NAT device, the internal device is identified by the public IP address and the dynamic port number. Dynamic NAT allows internal (private) hosts to contact external (public) hosts, but not vice versa. External hosts cannot initiate communications with internal hosts. DNS records associate a host name with an IP address. Multicast can forward a single data stream to all computers that are members of the same multicast group.
Which of the following best describes the purpose of using subnets? Subnets divide an IP network address into multiple network addresses. Subnets let you connect a private network to the internet. Subnets combine multiple IP network addresses into one network address. Subnets place each device within its own collision domain.
Subnets divide an IP network address into multiple network addresses. EXPLANATION Subnets divide an IP network address into multiple network addresses. This allows you to have several smaller networks while using only one network address.
You manage a subnet that uses the subnet address 198.162.1.0/23. Which of the following best describes how addressing is configured for the subnet? Supernetting Classful Private Subnetting
Supernetting EXPLANATION The subnet address 198.162.1.0/23 is an example of a supernetted address. With supernetting, multiple smaller subnets are combined into a single larger subnet. Supernetting is performed by taking the default subnet mask and making it smaller (using less bits). For this address, the default subnet mask uses 24 bits (255.255.255.0). With supernetting, the mask is altered to use only 23 bits (255.255.254.0) to combine multiple subnets together. Subnetting is the process of dividing a larger network into smaller networks. With the subnet address in this example, a subnetted address would use a larger subnet mask (using more bits). A subnetted address might use 25 bits (255.255.255.128) or more to subdivide the network into multiple smaller subnets. Sometimes the term "subnetting" can be used to refer to both subnetting and supernetting. But in this example, supernetting better describes what is being done. Classful addressing uses the default subnet mask based on the address class. If classful addressing were used, the subnet would use a 24-bit mask. Private addresses are within the following ranges: 10.0.0.1 to 10.255.255.254 172.16.0.1 to 172.31.255.254 192.168.0.1 to 192.168.255.254
Which of the following are true about routed firewalls? (Select two.) Supports multiple interfaces. Counts as a router hop. Easily introduced to an existing network. Internal and external interfaces connect to the same network segment. Operates at Layer 2.
Supports multiple interfaces. Counts as a router hop. EXPLANATION In a routed firewall, the firewall is also a Layer 3 router. In fact, many hardware routers include firewall functionality. Transmitting data through this type of firewall counts as a router hop. A routed firewall usually supports multiple interfaces, each connected to a different network segment. A transparent firewall (which is also called a virtual firewall) works differently. It operates at Layer 2 and is not seen as a router hop by connected devices. Both the internal and external interfaces on a transparent firewall connect to the same network segment. Because it is not a router, you can easily introduce a transparent firewall into an existing network.
What device is used to create a physical star topology? Bridge Firewall Switch Router
Switch EXPLANATION A physical star topology uses a switch or a hub. Routers are used to connect multiple subnets together. A firewall is a router that filters packets or other network communications.
Which of the following devices is used on a LAN and offers guaranteed bandwidth to each port? Router Hub Switch Bridge
Switch EXPLANATION A switch offers guaranteed bandwidth to each port.
Which of the following devices operates at the OSI model Layer 2? Router Switch Firewall Hub
Switch EXPLANATION A switch operates at the OSI model Layer 2 (Data Link layer). It reads the MAC address to make frame forwarding decisions. A hub operates at OSI model Layer 1 (Physical layer), while a router and a firewall operate at OSI model Layer 3 (Network layer).
Angela is the network administrator for a rapidly growing company with a 100BaseT network. Users have recently complained about slow file transfers. While checking network traffic, Angela discovers a high number of collisions. Which connectivity device would best reduce the number of collisions and allow future growth? Gateway Hub Router Switch Bridge
Switch EXPLANATION A switch would be the best choice in this situation. A bridge will segment traffic and reduce collisions, but it would be harder to maintain and harder to add new bridges as the network grows. A router would allow growth and reduce collisions. Switches can provide those benefits at a lower cost per port and offer more administration options.
Which of the following connectivity hardware is used to create a VLAN? Switch Bridge Hub Router
Switch EXPLANATION Specialized switches are used to create virtual LANs. The switch must be capable of appending and reading VLAN IDs.
You want to reduce collisions by creating separate collision domains and virtual LANs. Which of the following devices should you choose? Switch Active hub Bridge Router
Switch EXPLANATION Use a switch to create additional collision domains on a LAN. A switch filters an entire network and creates virtual LANs inside it rather than dividing it into separate internetworks as a router does.
You can create a virtual LAN using which of the following? Gateway Hub Router Switch
Switch EXPLANATION Use a switch to create virtual LANs (VLANs). The various ports on a switch can be assigned to a specific VLAN to create logically distinct networks on the same physical network topology. Routers, gateways, and hubs are common network devices, but they do not support the creation of VLANs.
When you configure VLANs on a switch, which of the following is used to identify a device's VLAN membership? Switch port MAC address IP address Host name
Switch port EXPLANATION VLAN membership is configured by assigning a switch port to a VLAN. A switch can have multiple VLANs configured on it, but each switch port can only be a member of a single VLAN. All devices connected to a switch port are members of the same VLAN.
Which of the following statements accurately describes a VLAN ID? VLAN IDs identify the VLAN where the frame originated so the receiving host can reply. VLAN IDs identify both the source and destination VLAN. They are like network addresses, except they exist at the Data Link layer. Switches append a VLAN ID to the header of each frame to identify the virtual network it belongs to. VLAN IDs are defined at the Network layer and help route the frame through the switch fabric.
Switches append a VLAN ID to the header of each frame to identify the virtual network it belongs to. EXPLANATION A VLAN ID is a unique identifier attached to each frame. Switches in the network understand the ID as they forward the frame. When the frame reaches its destination, the last switch removes the VLAN ID because no other device understands it. VLAN IDs work at the Data Link layer.
Which problem does the spanning tree protocol prevent? Switching loops from developing when redundant paths are implemented between switches. Buffer overflows by defining source-quench messages that a receiving device sends to the transmitting device. Packet blocking on backup bridge ports to allow switches to forward frames to all BPDUs. Routing tables from becoming outdated by decreasing the convergence time on a network.
Switching loops from developing when redundant paths are implemented between switches. EXPLANATION The spanning tree protocol is a long-standing protocol that runs in the background of bridged and switched networks to keep message loops from occurring.
Which of the following protocols includes extensive error checking to ensure that a transmission is sent and received without mistakes? TCP UCP UDB UDP
TCP EXPLANATION The TCP protocol includes error checking.
You are an application developer, and you are writing a program for exchanging video files through a TCP/IP network. You need to select a transport protocol that will guarantee delivery. Which TCP/IP protocol provides this capability? FTP UDP IP TFTP RIP TCP
TCP EXPLANATION Write the application to use the transmission control protocol (TCP). TCP guarantees delivery through error checking and acknowledgments.
Which protocols and port numbers are used by DHCP? (Select two.) TCP 69 TCP 67 UDP 123 UDP 69 UDP 67 TCP 123
TCP 67 UDP 67 EXPLANATION The dynamic host configuration protocol (DHCP) uses port 67 for both the TCP and UDP protocols. TFTP uses UDP port 69, and NTP uses UDP port 123.
Which of the following is a file transfer protocol that uses UDP? FTP SMTP HTTP POP3 TFTP NTP
TFTP EXPLANATION The trivial file transfer protocol (TFTP) uses UDP. The file transfer protocol (FTP) is a file transfer protocol, but uses TCP instead of UDP. HTTP is the hypertext transfer file. It is used for web browsing and is not considered a file transfer protocol. SMTP and POP3 are email transfer protocols. NTP is a service that provides network time.
Which of the following network services or protocols uses port 69? NNTP SMTP TFTP POP3
TFTP EXPLANATION The trivial file transfer protocol (TFTP) uses UDP/IP port 69. TFTP is a connectionless service for downloading files from a remote system. It is often used for downloading firmware to networking devices. The network news transfer protocol (NNTP) is used to access and download messages from newsgroup servers. NNTP uses TCP/IP port 119. The simple mail transfer protocol (SMTP) is used to send and receive email. SMTP uses TCP/IP port 25. The post office protocol version 3 (POP3) is used to download email from a remote system. POP3 uses TCP/IP port 110.
You want to transfer a file from a UNIX server to Windows Server 2016. Which of the following utilities could you use to do this? (Select all that apply.) Telnet Tracert TFTP NBTSTAT FTP Netsta
TFTP FTP EXPLANATION UNIX computers and Windows Server 2016 systems use TCP/IP. Therefore, the TCP/IP utilities FTP and TFTP both allow you to transfer files.
You are an administrator for a large company. You are setting up a computer at a worker's home so he can telecommute while he recovers from surgery. You want to connect to the UNIX server at the office to update his account information. Which utility should you use to accomplish this task? Traceroute Ping FTP Telnet
Telnet EXPLANATION Telnet allows you to perform terminal emulation, which means you can gain access to a host from a remote location and work as if you were at the actual host.
Match each troubleshooting command on the left with its function on the right. Each utility may be used once, more than once, or not at all. Drag: pathping ping -6 traceroute6 ping tracert Drop: Tests connectivity between two network hosts by sending IPv4 ICMP Echo Request packets without modifying the TTL parameter. Computes lost/sent packet statistics for each hop in the route between two hosts. Used on Linux systems to identify the route between two IPv6 hosts. Used on Windows systems to identify the route between two IPv4 hosts. Tests connectivity between two network hosts by sending IPv6 ICMP Echo Request packets without modifying the TTL parameter.
Tests connectivity between two network hosts by sending IPv4 ICMP Echo Request packets without modifying the TTL parameter. - ping Computes lost/sent packet statistics for each hop in the route between two hosts. - pathping Used on Linux systems to identify the route between two IPv6 hosts. - traceroute6 Used on Windows systems to identify the route between two IPv4 hosts. - tracert Tests connectivity between two network hosts by sending IPv6 ICMP Echo Request packets without modifying the TTL parameter. - ping -6 EXPLANATION Several commonly used network troubleshooting commands include the following: The pathping command combines the tracert and ping utilities to identify problems at a router or a network link. Unlike tracert or traceroute, pathping can track lost/sent packet statistics for each hop in the route between two hosts. The pathping command is only available on Windows. The ping command sends an IPv4 ICMP echo request/reply packet to a remote host. A response from the remote host indicates that both hosts are correctly configured and a connection exists between them. The ping command is available on Windows and Linux. The ping -6 command sends an IPv6 ICMP echo request/reply packet to a remote host. A response from the remote host indicates that both hosts are correctly configured and a connection exists between them. The ping -6 command is only available on Windows. On Linux, you would use ping6 instead. The tracert command uses ICMP packets to test the path between two IPv4 networks. Responses from each hop on the route are measured three times to provide an accurate representation of how long the packet takes to reach, and be returned by, the destination device. The tracert command is only available on Windows. On Linux, you would use traceroute instead. The traceroute6 command is used on Linux systems to identify the route between two IPv6 hosts.
You administer a web server on your network. The computer has multiple IP addresses. They are 192.168.23.8 to 192.168.23.17. The name of the computer is www.westsim.com. You configured the website as follows: IP address: 192.168.23.8 HTTP Port: 1030 SSL Port: 443 Users complain that they can't connect to the website when they type www.westsim.com. What is the most likely source of the problem? Clients are configured to look for the wrong IP address. FTP is not configured on the server. The HTTP port should be changed to 80. SSL is blocking internet traffic.
The HTTP port should be changed to 80. EXPLANATION The default HTTP port for the web is 80. You can change the default port; however, port 80 is the default port used by web browsers to make a connection to a web server. If you change the default port, the users must specify the correct port number, or they won't be able to connect to the server.
You have a small network connected to the internet as shown in the Exhibit. You need to configure the default gateway address on Wrk1 so that it can communicate with hosts on the internet. Which address would you use for the default gateway address? The IP address assigned to Fa0/0 on Router1. The IP address assigned to Fa0/0 on Router2. The IP address assigned to Fa0/1 on Router2. The IP address assigned to Fa0/1 on Router1. The IP address assigned to SwitchA.
The IP address assigned to Fa0/0 on Router1. EXPLANATION When assigning the default gateway address, use the address of the router interface connected to the same network that is used to reach remote networks. In this scenario, the workstation must be configured with the IP address assigned to the Fa0/0 interface on Router1. This default gateway configuration allows the workstation to communicate with hosts on the other internal subnet as well as with hosts on the network. The IP address assigned to the switch is only used to remotely manage the switch. Packets sent to remote networks are not processed by the switch, but the frames are forwarded to the correct destination device. The Fa0/1 interface on Router1 is not on the same network as Wrk1, so cannot be used as its default gateway address. The Fa0/0 interface on Router2 would be the default gateway address for hosts connected to SwitchB.
You are monitoring network traffic on your network, and you see traffic between two network hosts on port 2427. Which kind of network traffic uses this port? A workstation is using the DHCP protocol to request an IP address from a DHCP server. The MGCP protocol is generating traffic, which VoIP uses to send voice data over a network. Someone is remotely accessing another system using the SSH protocol. A ping of death attack on a network host is in progress.
The MGCP protocol is generating traffic, which VoIP uses to send voice data over a network. EXPLANATION Someone on the network is using voice over IP (VoIP) to make a telephone call. Some VoIP implementations use the media gateway control protocol (MGCP) to set up, maintain, tear down, and redirect calls. MGCP uses port 2427. The DHCP protocol is used to automatically assign IP addresses to network hosts and utilizes IP ports 67 and 68. A ping of death attack utilizes an oversized ICMP echo request packet to crash a target system. The SSH protocol is used to remotely access another network host and uses port 22.
A small startup company has hired you to harden their new network. Because funds are limited, you have decided to implement a unified threat management (UTM) device that provides multiple security features in a single network appliance: Firewall VPN Anti-spam Antivirus You join the UTM device to the company's Active Directory domain. The company's traveling sales force will use the VPN functionality provided by the UTM device to connect to the internal company network from hotel and airport public Wi-Fi networks. Which weaknesses exist in this implementation? Remote users should not establish VPN connections to the internal network using public Wi-Fi networks. The UTM device should not be joined to the Active Directory domain. Anti-spam and antivirus functions must be placed on separate servers. The UTM represents a single point of failure.
The UTM represents a single point of failure. XPLANATION A unified threat management device combines multiple security features into a single network appliance. A single UTM device can provide several security features: Firewall VPN Ant-spam Anti-virus Load balancing By combining several services into one appliance, UTM devices make managing network security less expensive and complex. However, they also introduce a single point of failure—if the UTM fails, then network security is lost. Additionally, UTM devices aren't as robust as other devices made for a specific use. Therefore, UTM devices are best suited for: Offices where space limits don't allow multiple security appliances. Satellite offices that need to be managed remotely. Configuration changes need to be made on only one device, rather than multiple devices. Smaller businesses that wouldn't benefit from the robust features provided by specific security appliances. Joining the UTM device to the Active Directory domain is the best practice because it simplifies authentication management. Using a VPN connection while accessing a public Wi-Fi network is a good practice because it provides an extra layer of security. Since this organization is a small startup, combining anti-spam and anti-virus functions on the same device is an acceptable practice.
After installing a new DHCP server on the network, you need to verify that network devices are receiving IP addressing via DHCP. You reboot a Windows 10 client system and using the ipconfig /all command, receive the following information: Ethernet adapter Local Area Connection 1: Description . . . . . . . . . . . : Intel(R) Ethernet Connection Physical Address. . . . . . . . . : 02-00-4C-4F-3F-50 DHCP Enabled. . . . . . . . . . . : Yes Autoconfiguration Enabled . . . . : Yes Autoconfiguration IPv4 Address. . : 169.254.25.129 Subnet Mask . . . . . . . . . . . : 255.255.0.0 Default Gateway . . . . . . . . . : DNS Servers . . . . . . . . . . . : Which of the following statements are true? (Select two). The default gateway address needs to point to the DHCP server. The network is configured to use static IP addressing. The network subnet mask is incorrect. The client system is configured to use DHCP. The client system is unable to reach the DHCP server. DHCP is disabled on the client system.
The client system is configured to use DHCP. The client system is unable to reach the DHCP server. EXPLANATION A system configured as a DHCP client will attempt to locate a DHCP server during the boot process. If the client system is unable to locate the DHCP server and obtain IP information, an APIPA assigned address will be used. The client also configures itself with a class B subnet mask of 255.255.0.0. The output from the ipconfig command shows that the client system has been configured to receive IP information from a DHCP server. As such, the client system attempted to locate the DHCP server. When it couldn't, received the APIPA address of 169.254.25.129 and a subnet mask of 255.255.0.0. The default gateway does not have to be present to access a DHCP server.
Due to widespread network expansion, you have decided to upgrade the network by configuring a DHCP server. The network uses Linux, Windows, and Mac OS X client systems. You configure the server to distribute IP addresses from 192.168.2.1 to 192.168.2.100. You use the subnet mask of 255.255.255.0. After making all setting changes on the DHCP server, you reboot each client system, but they are not able to obtain an IP address from the DHCP server. Which of the following would explain the failure? DHCP does not work in a heterogeneous computing environment unless the DHCP Samba client software is installed. DHCP does not function in a heterogeneous computing environment. The DHCP server must be rebooted. The clients must be configured to obtain IP addressing from a DHCP server. 192.168.x.x requires a class C subnet mask.
The clients must be configured to obtain IP addressing from a DHCP server. EXPLANATION Once a DHCP server has been configured for the network, each client system has to be told to look for a DHCP server to obtain its IP addressing. Selecting DHCP to obtain IP addressing information is typically as easy as selecting a radio button. If the client is not set to DHCP, it will look for a statically assigned IP address. The DHCP service is supported by all major operating systems today. Using DHCP among different client systems would not be a problem. Rebooting the DHCP server would not be helpful if the client systems are not configured to use the DHCP service.
A network is connected following the IEEE 802.3 specifications. Which of the following best describes when a device can transmit messages? The device transmits whenever it is ready. The device listens to determine if the transmission media is free. The device requests permission from a controlling device. The device is notified of its turn to send messages. The device with the token can use the transmission media
The device listens to determine if the transmission media is free. EXPLANATION The IEEE 802.3 committee describes the CSMA/CD media access method. Devices listen to the network to determine if the transmission media is free before transmitting.
Which of the following describe the EDGE cellular technology? (Select two.) The first internet-compatible technology Offers speeds of 400-1,000 Kbps An extension to 3G Uses MIMO
The first internet-compatible technology Offers speeds of 400-1,000 Kbps EXPLANATION The EDGE cellular technology was an intermediary between 2G and 3G networks. EDGE was the first cellular technology to be truly internet-compatible and has speeds of 400-1,000 Kbps. MIMO is used by HSPA+, LTE, and 4G networks.
What information does the next hop entry in a routing table identify? The last router in the path to the destination network. A backup router that is used to forward packets addressed to unknown networks. The number of routers that the packet must go through to reach the destination network. The first router in the path to the destination network.
The first router in the path to the destination network. EXPLANATION The next hop router is the first (or next) router in the path to the destination network. Each router looks at the destination network in the packet, then consults the routing table to identify the next hop router to the destination network. The hop count identifies the number of routers in the path to the destination network. A default gateway router is a router that is used for packets sent to external networks. Most routers do not have a default gateway setting, but instead use a default route setting, which identifies a next hop router for all unknown networks.
If dynamic DNS is being used, which of the following events will cause a dynamic update of the host records? (Select two.) An MX record is added to the DNS server. The browser cache on a workstation is cleared. The ipconfig /registerdns command is entered on a workstation. The DHCP server renews an IP address lease. A CNAME record is added to the DNS server.
The ipconfig /registerdns command is entered on a workstation. The DHCP server renews an IP address lease. EXPLANATION Dynamic DNS (DDNS) enables clients or the DHCP server to update records in the zone database automatically. Dynamic updates occur when: A network host's IP address is added, released, or changed. The DHCP server changes or renews an IP address lease. The client's DNS information is manually changed using the ipconfig /registerdns command. Clearing a browser's cache has no effect on DNS records. Because MX records and CNAME records need to be manually added and created, they have no effect on DDNS.
Which of the following are true regarding using multiple VLANs on a single switch? (Select two.) The number of collision domains decreases. The number of broadcast domains decreases. The number of collision domains increases. The number of broadcast domains remains the same. The number of broadcast domains increases. The number of collision domains remains the same.
The number of broadcast domains increases. The number of collision domains remains the same. EXPLANATION When you configure multiple VLANs on a single switch, the number of broadcast domains increases. Each VLAN will be placed in its own broadcast domain. The number of collision domains remains the same. Each switch port is its own collision domain regardless of the number of VLANs configured on the switch.
Which of the following are true regarding cloud computing? (Select three.) Cloud computing requires end user knowledge of the physical location and configuration of the system that delivers the services. The term "cloud" is used as a synonym for the internet. Typical cloud computing providers deliver common business applications online that are accessed from another web service or software like a web browser. Cloud computing is software, data access, computation, and storage services provided to clients through the internet.
The term "cloud" is used as a synonym for the internet. Typical cloud computing providers deliver common business applications online that are accessed from another web service or software like a web browser. Cloud computing is software, data access, computation, and storage services provided to clients through the internet. EXPLANATION Cloud computing does not require end user knowledge of the physical location and configuration of the system that delivers the services. Other cloud computing details include the following: Cloud computing is software, data access, computation, and storage services provided to clients through the internet. The term "cloud "is used as a synonym for the internet based on the basic cloud drawing used to represent the telephone network infrastructure (and, later, the internet) in computer network diagrams. Typical cloud computing providers deliver common business applications online that are accessed from another web service or software like a web browser, while the software and data are stored on servers.
Your organization uses an 802.11b wireless network. Recently, other tenants installed the following equipment in your building: A wireless television distribution system running at 2.4 GHz A wireless phone system running at 5.8 GHz A wireless phone system running at 900 MHz An 802.11a wireless network running in the 5.725 - 5.850 GHz frequency range An 802.11j wireless network running in the 4.9 - 5.0 GHz frequency range Since this equipment was installed, your wireless network has been experiencing significant interference. Which system is to blame? The 5.8 GHz wireless phone system The wireless TV system The 802.11j wireless network The 900 MHz wireless phone system The 802.11a wireless network
The wireless TV system EXPLANATION Because the 802.11b standard operates within the 2.4 GHz to 2.4835 GHz radio frequency range, the most likely culprit is the wireless TV distribution system.
You are monitoring network traffic on your network. You see a large amount of traffic between a Windows workstation and a Windows server on the following ports: 137 138 139 What is the source of this network traffic? A denial of service (DoS) attack on the server is in progress. The workstation is synchronizing its local time with the time on the server. The workstation is using NetBIOS to access shared resources on the server. The workstation is accessing messages from the email service on the server.
The workstation is using NetBIOS to access shared resources on the server. EXPLANATION The workstation is using NetBIOS to access shared resources on the server, such as shared folders and printers. The NetBIOS protocol uses three ports: 137 138 139 Email clients use the POP (port 110) or IMAP (port 143) protocols to access messages on an email server. The NTP protocol (port 123) is used to synchronize time between network hosts. A denial of service (DoS) attack utilizes characteristics of the TCP or ICMP protocols to flood a network host with so much traffic that it can't respond to network requests.
While viewing the status of the interfaces on a Cisco switch, you see an abnormally large number of oversized Ethernet frames being received on one interface. This interface is connected to a workstation located on the second floor. What could cause this to happen? An incorrect subnet mask has been configured on the workstation. Collisions between two or more network hosts are occurring. Two hosts on the network have the same MAC address. The workstation's network board is jabbering. A strong EMI emitter is near the cable that connects the workstation to the interface.
The workstation's network board is jabbering. EXPLANATION Frames that are too long are typically caused by a faulty network card that jabbers (constantly sending garbage data). On a hub-based Ethernet network, these errors could possibly be caused by collisions. However, because a switch is being used in this scenario, collisions can't occur. EMI or cross-talk on the UTP cabling would cause corrupted frames and result in CRC errors. Oversize frame errors are Layer 1 errors. Duplicate MAC addresses would result in a Layer 2 error. Incorrect protocol or IP addressing configurations would result in Layer 3 errors.
What is the risk associated with smart technology used in networked devices such as smart refrigerators, environmental controls, or industrial equipment? They are vulnerable to exploits due to weaker security. They use redundant paths for fault tolerance that can cause message loops to develop on the network. They are not physically secure, so they can be reconfigured by anyone who has access to them. They are not compatible with routing protocols, which causes a burden on network bandwidth.
They are vulnerable to exploits due to weaker security. EXPLANATION Devices with embedded smart technology are not designed to be customized or directly configured by system administrators. For example, you cannot install anti-malware software on a smart TV. Because of this weaker security, smart technology devices are vulnerable to exploits and attacks.
Which of the following technologies does GSM use to allow multiple connections on the same frequency? Multiple-input and multiple-output Time division multiple access Frequency division multiple access Code division multiple access
Time division multiple access EXPLANATION GSM uses time division multiple access (TDMA) to allow multiple connections on the same frequency. Code division multiple access (CDMA) is not used by GSM, but it is the technology used by most mobile service providers in the United States. Multiple-input and multiple-output (MIMO) is a method for increasing data throughput and link range. Frequency division multiplexing (FDMA) is used primarily for satellite communications.
What purposes does a wireless site survey fulfill? (Choose two.) To document existing infrared traffic in the 5.4 GHz spectrum. To identify the coverage area and preferred placement of access points. To identify the recommended 100 degree separation angle for alternating access points. To identify existing or potential sources of interference.
To identify the coverage area and preferred placement of access points. To identify existing or potential sources of interference. EXPLANATION Wireless site surveys provide layout and design parameters for access point coverage and placement. Site surveys can also identify rogue access points and other forms of interference that reduce security and prevent the proper operation of authorized network devices. Radio frequency spectrum and protocol analyzers are used to conduct the surveys.
Which OSI model layer is responsible for guaranteeing reliable message delivery? Application Data Link Session Transport
Transport EXPLANATION The Transport layer is responsible for connection services that provide reliable message delivery through error detection and correction mechanisms. Specifically, the TCP protocol provides these services. The Application layer integrates network functionality into the host operating system and enables network services. The Session layer's primary function is managing the sessions in which data is transferred. The Data Link layer defines the rules and procedures for hosts as they access the Physical layer.
When configuring VLANs on a switch, what type of switch ports are members of all VLANs defined on the switch? Any port not assigned to a VLAN. Gigabit and higher Ethernet ports. Uplink ports. Trunk ports. Each port can only be a member of a single VLAN.
Trunk ports. EXPLANATION A trunk port is a member of all VLANs defined on a switch and carries traffic between the switches. When trunking is used, frames that are sent over a trunk port are tagged by the first switch with the VLAN ID so that the receiving switch knows which VLAN the frame belongs to. Typically, uplink ports (which are faster than the other switch ports) are used for trunk ports, although any port can be designated as a trunking port. On an unconfigured switch, ports are members of a default VLAN (often designated VLAN 1). When you remove a port's VLAN membership, it is reassigned back to the default VLAN. Therefore, the port is always a member of one VLAN.
You manage a network with two switches. The switches are connected together through their Gigabit Ethernet uplink ports. You define VLAN 1 and VLAN 2 on each switch. A device on the first switch in VLAN 1 needs to communicate with a device on the second switch in VLAN 1. What should you configure to allow communication between these two devices through the switches? Spanning tree Trunking Bonding Layer 3 switching
Trunking EXPLANATION A trunk port is used to connect two switches together. Typically, Gigabit Ethernet ports are used for trunk ports, although any port can be a trunking port. A trunk port is a member of all VLANs and carries traffic between the switches. When trunking is used, frames that are sent over a trunk port are tagged by the first switch with the VLAN ID so that the receiving switch knows which VLAN the frame belongs to. The trunking protocol describes the format that switches use for tagging frames with the VLAN ID. Because end devices do not understand the VLAN tags, the tag is removed from the frame by the switch before the frame is forwarded to the destination device. VLAN tagging is only used for frames that travel between switches on the trunk ports. Use a Layer 3 switch or a router to enable devices in different VLANs to communicate with each other. Spanning tree is a protocol on a switch that allows it to maintain multiple paths between switches within a subnet. The spanning tree protocol runs on each switch and is used to select a single path between any two switches. Bonding allows multiple switch ports to be used at the same time to reach a specific destination.
You manage a single subnet with three switches. The switches are connected to provide redundant paths between the switches. Which feature allows the switches to pass VLAN traffic between the switches? Bonding Trunking Spanning tree 802.1x PoE
Trunking EXPLANATION A trunk port is used to connect two switches together. A trunk port is a member of all VLANs and carries traffic between the switches. When trunking is used, frames that are sent over a trunk port are tagged by the first switch with the VLAN ID so that the receiving switch knows which VLAN the frame belongs to. The trunking protocol describes the format that switches use for tagging frames with the VLAN ID. Because end devices do not understand the VLAN tags, the tag is removed from the frame by the switch before the frame is forwarded to the destination device. 802.1x is an authentication protocol used with port security (or port authentication). Spanning tree is a protocol on a switch that allows the switch to maintain multiple paths between switches within a subnet. The spanning tree protocol runs on each switch and is used to select a single path between any two switches. Power over Ethernet (PoE) supplies power to end devices through the RJ45 Ethernet switch port. Bonding groups multiple switch ports into a single logical port, allowing both ports to be used to communicate with a single device.
Which of the following are characteristics of Teredo tunneling? (Select three.) IPv4-only hosts communicate with IPv6-only hosts. Tunnel endpoints configured on hosts. Dual stack hosts. Dual stack routers. Works through NAT.
Tunnel endpoints configured on hosts. Dual stack hosts Works through NAT. EXPLANATION Teredo tunneling has the following characteristics: Tunnel endpoints are configured on hosts. Hosts are dual-stack hosts and perform tunneling to send IPv6 packets on the IPv4 network. Works through NAT. The only solution that allows IPv4-only hosts to communicate with IPv6-only hosts is network address translation-protocol translation (NAT-PT).
Which protocol and port number is used by TFTP? UDP 67 TCP 20 and 21 TCP 69 UDP 20 and 21 TCP 67 UDP 69
UDP 69 EXPLANATION The trivial file transfer protocol (TFTP) uses UDP port 69. TFTP is a faster alternative to FTP. TFTP uses UDP instead of TCP to reduce the overhead of sending packets. FTP uses TCP ports 20 and 21. DHCP uses port 67.
Which type of address is used in a packet to address the packet to a single host? Simplex Full-duplex Multicast Unicast Broadcast
Unicast EXPLANATION A unicast address is an address that identifies a single host. A broadcast address is an address that is sent to all hosts. Broadcast traffic is typically only forwarded within (but not between) a subnet. A multicast address is an address that identifies a group of computers. Members of the group share the same multicast address. Simplex communication uses a single channel for both sending and receiving. Full-duplex has a dedicated send and receive channel between any two hosts.
Which type of address is the IP address 198.162.12.254/24? Unicast Broadcast Multicast Private
Unicast EXPLANATION The address 198.162.12.254 is a unicast address that identifies a single host on the 198.162.12.0 subnet. 198.162.12.255 is the broadcast address for the subnet. Multicast addresses are in the range of 224.0.0.0 to 239.255.255.255. The private IPv4 address ranges are: 10.0.0.1 to 10.255.255.254 172.16.0.1 to 172.31.255.254 192.168.0.1 to 192.168.255.254
Which of the following strategies are used to prevent duplicate IP addresses being used on a network? (Select two.) Use Automatic Private IP Addressing. Install a DHCP server on the network. Configure a HOSTS file for local IP resolution. Configure client systems to use static IP assignment. Install the DHCP client on all workstations. Set the Windows network-monitoring utility to identify potential IP conflicts.
Use Automatic Private IP Addressing. Install a DHCP server on the network. EXPLANATION To avoid duplicate IP addresses being used by network systems, automatic IP assignment is used. Both the DHCP service and APIPA can automatically assign addresses to client systems. Clients configured to use static IP addressing may inadvertently have duplicate IP addresses assigned to them. In such a case, one of the systems will not be able to log on to the network.
You manage a network with a single switch. All hosts connect to the network through the switch. You want to increase the security of devices that are part of the accounting department. You want to make sure that broadcast traffic sent by accounting computers is only received by other accounting computers, and you want to implement ACLs to control traffic sent to and between accounting computers through the network. Which of the following is the BEST solution? Use a router to configure a subnet for the accounting computers. Configure MAC address filtering on the switch for the accounting computers. Implement NAC with 802.1x authentication for the accounting computers. Configure a VLAN on the switch for the accounting computers.
Use a router to configure a subnet for the accounting computers. EXPLANATION To separate broadcast traffic and filter network traffic with access control lists (ACLs), use a router to create an additional subnet for the accounting computers. You could use a VLAN to separate broadcast traffic for the accounting computers, but the ACL, would not be able to filter traffic within the VLAN. Use network access control (NAC) to allow only devices that meet specific health requirements (such as having anti-virus or patches) to connect to the network. Use MAC filtering on a switch to allow or deny access through the switch based on the connecting device's MAC address.
You have a company network that is connected to the internet. You want all users to have internet access, but you need to protect your private network and users. You also need to make a web server publicly available to internet users. Which solution should you use? Use a single firewall. Put the web server in front of the firewall and the private network behind the firewall. Use firewalls to create a DMZ. Place the web server inside the DMZ and the private network behind the DMZ. Use a single firewall. Put the web server and the private network behind the firewall. Use firewalls to create a DMZ. Place the web server and the private network inside the DMZ.
Use firewalls to create a DMZ. Place the web server inside the DMZ and the private network behind the DMZ. EXPLANATION A demilitarized zone (DMZ), also called a screened subnet, is a buffer network (or subnet) that sits between the private network and an untrusted network, such as the internet. A common configuration uses two firewalls, one connected to the public network, and one connected to the private network. Publicly accessible resources (servers) are placed inside the screened subnet. Examples of publicly accessible resources include web, FTP, or email servers. Private resources that are not accessible from the internet are placed behind the DMZ (behind the inner firewall). Placing the web server inside the private network would mean opening ports in the firewall leading to the private network, which could expose other devices to attack. Placing the web server outside of the firewall would leave it unprotected.
Match the wireless signaling method on the left with its definition on the right. (Not all of the signaling methods match a definition.) Drag: OFDM CDMA DSSS FHSS Drop: Uses a narrow frequency band and hops data signals in a predictable sequence Breaks data into pieces and sends the pieces across multiple frequencies in a defined range. Breaks data into very small data streams in order to send the information across long distances.
Uses a narrow frequency band and hops data signals in a predictable sequence - FHSS Breaks data into pieces and sends the pieces across multiple frequencies in a defined range. - DSSS Breaks data into very small data streams in order to send the information across long distances. - OFDM EXPLANATION The following table describes the most common signaling methods used by wireless networks. Frequency Hopping Spread Spectrum (FHSS): FHSS uses a narrow frequency band and hops data signals in a predictable sequence from frequency to frequency over a wide band of frequencies. Direct-Sequence Spread Spectrum (DSSS): DSSS uses a transmitter that breaks data into pieces and sends the pieces across multiple frequencies in a defined range. DSSS is more susceptible to interference and less secure then FHSS. Orthogonal Frequency-Division Multiplexing (OFDM): OFDM breaks data into very small data streams in order to send the information across long distances where environmental obstacles may be an issue.
You run a small network for your business that has a single router connected to the internet and a single switch. You keep sensitive documents on a computer that you would like to keep isolated from other computers on the network. Other hosts on the network should not be able to communicate with this computer through the switch, but you still need to access the network through the computer. What should you use for this situation? VPN VLAN Spanning tree Port security
VLAN EXPLANATION Define virtual LANs (VLANs) on the switch. With a VLAN, a port on the switch is associated with a VLAN. Only devices connected to ports that are members of the same VLAN can communicate with each other. Routers are used to allow communication between VLANs if necessary. Use virtual private network (VPN) to connect two hosts securely through an unsecured network (such as the internet). VPN tunneling protocols protect data as it travels through the unsecured network. Spanning tree is a switch feature that allows redundant paths between switches. Port security is a method of requiring authentication before a network connection is allowed.
You run a small network for your business that has a single router connected to the internet and a single switch. You keep sensitive documents on a computer that you would like to keep isolated from other computers on the network. Other hosts on the network should not be able to communicate with this computer through the switch, but you still need to access the network through the computer. Which of the following should you use in this situation? VLAN Spanning tree Port security VPN
VLAN EXPLANATION You should define virtual LANs (VLANs) on the switch. With a VLAN, a port on the switch is associated with a VLAN. Only devices connected to ports that are members of the same VLAN can communicate with each other. Routers are used to allow communication between VLANs if necessary. Use a virtual private network (VPN) to connect two hosts securely through an unsecured network (such as the internet). VPN tunneling protocols protect data as it travels through the unsecured network. Spanning tree is a switch feature that allows for redundant paths between switches. Port security is a method of requiring authentication before a network connection is allowed.
Your company is a small start-up that has leased office space in a building shared by other businesses. All businesses share a common network infrastructure. A single switch connects all devices in the building to the router that provides internet access. You would like to make sure that your computers are isolated from computers used by other companies. Which feature should you request to have implemented? VLAN VPN Port security Spanning tree
VLAN EXPLANATION You should define virtual LANs (VLANs) on the switch. With a VLAN, a port on the switch is associated with a VLAN. Only devices connected to ports that are members of the same VLAN can communicate with each other. Routers are used to allow communication between VLANs if necessary. Use virtual private network (VPN) to connect two hosts securely through an unsecured network (such as the internet). VPN tunneling protocols protect data as it travels through the unsecured network. Spanning tree is a switch feature that allows for redundant paths between switches. Port security is a method of requiring authentication before a network connection is allowed.
Which switch features are typically used with VoIP? (Select two.) Mirroring VLAN Spanning tree PoE
VLAN PoE EXPLANATION When configuring Voice over IP (VoIP), switches with Power over Ethernet (PoE) capabilities provide power to the VoIP phone through an Ethernet cable, the same cable that is used for transmitting data signals. Virtual LANs (VLANs) are often used to distinguish voice traffic from data traffic so that Quality of Service (QoS) measures can be applied to traffic that is part of the voice VLAN. Bonding allows multiple switch ports to be used at the same time to reach a specific destination. Spanning tree is a protocol on a switch that allows the switch to maintain multiple paths between switches within a subnet. The spanning tree protocol runs on each switch and is used to select a single path between any two switches. Mirroring sends traffic from all switch ports to a switch port you designate as the mirrored port.
You need to keep users in all other departments from accessing the servers used by the finance department. Which of the following technologies should you use to logically isolate the network? Subnetting NIC teaming MAC filtering VLANs
VLANs EXPLANATION A virtual LAN (VLAN) uses switch ports to define a broadcast domain. When you define a VLAN, you assign devices on different switch ports to a separate logical, or virtual, LAN. NIC teaming is used to combine two or more physical connections into one logical connection and does not isolate networks. While MAC filtering could be used to control access, it is easily bypassed by MAC spoofing. Subnetting is used to divide large networks into smaller networks. Subnetting can be used to isolate sensitive systems, but a subent is not as secure as a VLAN.
You manage a network that uses a single switch. All ports within your building connect through the single switch. In the lobby of your building are three RJ45 ports connected to the switch. You want to allow visitors to plug into these ports to gain internet access, but they should not have access to any other devices on your private network. Employees connected throughout the rest of your building should have both private and internet access. Which feature should you implement? NAT VLANs DMZ Port authentication
VLANs EXPLANATION Use VLANs to segregate hosts based on switch ports. You can define two VLANs, one for employees connected throughout the building, and another for the ports in the lobby. The ports in the lobby would have only internet access, while devices connected to ports in the rest of the building could communicate with other devices within the same VLAN. Use port authentication to control access to the network based on things such as username and password. Port authentication would allow or deny access, but would not restrict access once authenticated or provide any type of access if not authenticated. A demilitarized zone (DMZ) is a buffer network (or subnet) that sits between the private network and an untrusted network (such as the internet). Network address translation (NAT) modifies the IP addresses in packets as they travel from one network (such as a private network) to another (such as the internet). NAT allows you to connect a private network to the internet without obtaining registered addresses for every host. Hosts on the private network share the registered IP addresses.
You manage a network that uses a single switch. All ports within your building connect through the single switch. In the lobby of your building are three RJ45 ports connected to the switch. You want to allow visitors to plug into these ports to gain internet access, but they should not have access to any other devices on your private network. Employees connected throughout the rest of your building should have both private and internet access. Which feature should you implement? Port authentication VLANs Spanning tree PoE
VLANs EXPLANATION Use VLANs to segregate hosts based on switch ports. You could define two VLANs, one for employees connected throughout the building, and another for the ports in the lobby. The ports in the lobby would have only internet access, while devices connected to ports in the rest of the building could communicate with other devices within the same VLAN. Use port authentication to control access to the network based on things such as username and password. Port authentication would allow or deny access, but would not restrict access once authenticated or provide any type of access if not authenticated. Spanning tree is a protocol on a switch that allows the switch to maintain multiple paths between switches within a subnet. The spanning tree protocol runs on each switch and is used to select a single path between any two switches. Power over Ethernet (PoE) supplies power to end devices through the RJ45 Ethernet switch port.
Which of the following terms describes a test lab environment that does not require the use of physical hardware? Offsite virtual storage Network as a service (NaaS) Virtual sandbox VLAN
Virtual sandbox EXPLANATION A virtual sandbox is a virtual environment that can be used to test new deployments and software updates without affecting the production environment. Offsite virtual storage is used to store files and documents on a remote network. Network as a service (NaaS) is a network implementation contracted by a third party. NaaS virtualizes the entire network infrastructure of a production environment. Switches use VLANs to create separate logical LANs.
A router is connected to network 192.168.1.0/24 and network 192.168.2.0/24. The router is configured to use RIP and has learned of networks 192.168.3.0/24 and 192.168.4.0/24. The next hop router for network 192.168.3.0 has changed. You need to make the change with the least amount of effort possible. What should you do? Wait for convergence to take place. Stop and restart the RIP protocol on the router. Force RIP to perform an immediate update. Manually reconfigure the default route to point to the new next hop router.
Wait for convergence to take place. EXPLANATION When using a routing protocol, changes in routing information take some time to be propagated to all routers on the network. The term "convergence" is used to describe the condition when all routers have the same (or correct) routing information. Static routes in the routing table must be updated manually. Restarting RIP might actually increase the time required for changes to be learned. Forcing an update (if the router supports it) is not a requirement, as the periodic sharing of routes will eventually update the routing table entry.
You are configuring a firewall to allow access to a server hosted on the demilitarized zone of your network. You open TCP/IP ports 80, 25, 110, and 143. Assuming that no other ports on the firewall need to be configured to provide access, which applications are most likely to be hosted on the server? Web server, DNS server, and email server Web server and email server Web server, DNS server, and DHCP server Email server, Newsgroup server, and DNS server
Web server and email server EXPLANATION TCP/IP port 80 is associated with accessing web pages from a web server using the hypertext transfer protocol (HTTP). Email can be accessed using a number of protocols, including the simple mail transfer protocol (SMTP), the post office protocol version 3 (POP3) and the internet message access protocol version 4 (IMAP4). SMTP uses TCP/IP port 25, while POP3 uses TCP/IP port 110, and IMAP4 uses TCP/IP port 143. Domain name service (DNS) traffic uses TCP/IP port 53. Newsgroup servers are accessed using the network news transfer (NNTP) protocol on TCP/IP port 119. Dynamic host configuration protocol (DHCP) traffic uses the BOOTP protocol on TCP/IP ports 67 and 68.
Which of the following forms of networking are highly susceptible to eavesdropping and must be secured accordingly? Dial-up Satellite Wireless DSL ISDN
Wireless EXPLANATION All forms of networking are potentially vulnerable to eavesdropping. Wireless networks by definition broadcast network transmissions openly and therefore can be detected by outsiders. For this reason, wireless networks should maintain data encryption to minimize the risk of transmitting information to unintended recipients. Other forms of networking, while potentially susceptible to eavesdropping, cannot be detected as readily as wireless.
Which of the following benefits apply only to creating VLANs with switches and not to segmenting the network with regular switches? You can provide guaranteed bandwidth between two devices. You can create multiple collision domains. You can create multiple broadcast domains. You can segment the network based on physical location.
You can create multiple broadcast domains. EXPLANATION By creating a VLAN, you create multiple broadcast domains, with each VLAN being in its own broadcast domain. Using switches without VLANs lets you segment the network based on physical location, create multiple collision domains, and provide guaranteed bandwidth between devices.
You are implementing a DHCP server for your segment. Your segment's IP address is 192.168.1.0. Your default gateway address is 192.168.1.254. Your DNS server address is 192.168.1.1. Your default gateway is configured as a NAT router to translate addresses between network segments. You configured the 03 Router option on your DHCP server so it can deliver the IP address of the default gateway to workstations. After configuring your workstations to get their IP addressing information dynamically, your users complain that they are unable to access websites on the internet. How can you resolve this problem? You must configure your DHCP server with an option that delivers the IP address of the DNS server (Option 06). You must configure your DHCP server with an option that enables IP forwarding (Option19). You must configure your DHCP server with an option that delivers the IP address of the default World Wide Web server (Option 72). You must configure Automatic Private IP Addressing (APIPA) on each workstation using default settings. You must implement a BOOTP server instead of a DHCP server. You can't implement a DHCP server in conjunction with a NAT router.
You must configure your DHCP server with an option that delivers the IP address of the DNS server (Option 06). EXPLANATION In this scenario, the DHCP server hasn't been configured to deliver the IP address of the DNS server to the workstations. When users try to access websites with a browser, they receive an error message because their workstations can't resolve URLs into IP addresses. To fix this problem, you must enable the 06 Domain Name Server option on the DHCP server and configure it with the IP address of your DNS server. You could statically configure APIPA on each workstation with the IP address of the DNS server, but doing this would defeat the purpose of implementing a DHCP server in the first place.
In which of the following situations would you most likely implement a demilitarized zone (DMZ)? You want internet users to see a single IP address when accessing your company network. You want to encrypt data sent between two hosts using the internet. You want to protect a public web server from attack. You want to detect and respond to attacks in real time.
You want to protect a public web server from attack. EXPLANATION Use a demilitarized zone (DMZ) to protect public hosts on the internet, such as a web server, from attack. The DMZ uses an outer firewall that prevents internet attacks. Inside the DMZ are all publicly accessible hosts. A second firewall protects the private network from the internet. Use a virtual private network (VPN) to encrypt data between two hosts on the internet. Use Network address translation (NAT) to hide internal IP addresses from the internet. Use an intrusion prevention system (IPS) to detect and respond to threats in real time.
Which protocol is well known for its use in the the home security and home automation industry, uses a mesh topology, makes devices act as repeaters, and has a low data transfer rate? Z-Wave 802.11 AC NFC Ant+
Z-Wave EXPLANATION The Z-Wave protocol is mostly used in the home security and automation market and uses only a mesh topology. Each device that is added acts as a repeater and increase the strength of the network. Z-Wave has a low data transfer rate. Ant+ is can be used in a mesh topology, but is generally used to monitor sensor data. NFC is commonly used for mobile pay solutions and connections like blue tooth, but has to be several inches within another device to connect. 802.11 AC is a wireless networking standard that offers high-speed data transfer.
You need to configure a Cisco RFC 1542-compliant router to forward any received DHCP frames to the appropriate subnet. The address of the remote DHCP server is 172.16.30.1 Which of the following commands would you use to configure the router? ip address dhcp 172.16.30.1 ip helper-address 172.16.30.1 host 172.16.30.1 ifconfig 172.16.30.1
ip helper-address 172.16.30.1 EXPLANATION To configure a Cisco router to listen for DHCP traffic and route any received DHCP frames to the appropriate subnet, use the following command: ip helper-address [server_address] The ifconfig command is used on a Linux computer to display TCP/IP configuration information. The host command is used to query the A records of a specified host. The ip address dhcp command is used to configure a Cisco switch to obtain its IP address from a DHCP server.
Which of the following utilities would you use to view the routing table? dig mtr tracert traceroute route
route EXPLANATION Use the route command to display the contents of the routing table and to add or remove static routes. traceroute, or tracert, uses ICMP packets to test connectivity between devices and shows the path between the two devices. Responses from each hop on the route are measured three times to provide an accurate representation of how long the packet takes to reach and be returned by that host. The mtr command on Linux is a combination of the ping and traceroute commands. The dig command resolves (looks up) the IP address of a host name.
Which of the following commands would display the output shown here? mtr ifconfig host route print
route print EXPLANATION Use the route print or netstat -r commands to display the contents of the routing table. The mtr command performs a test that is like a combination of the ping and traceroute commands. The host command resolves host names to IP addresses. The ifconfig command shows the IP configuration on a Linux computer.
The network board in a workstation is currently configured as follows: Network speed = Auto Duplexing = Auto The workstation is experiencing poor network performance, and you suspect that the network board is not correctly detecting the network speed and duplex settings. Upon investigation, you find that it is running at 10 Mbps half-duplex. You know that your network switch is capable of much faster throughput. To fix this issue, you decide to manually configure these settings on the workstation. Before you do so, you need to verify the configuration of the switch port that the workstation is connected to. Given that it is a Cisco switch, which commands can be used on the switch to show a list of all switch ports and their current settings? (Select two.) show interface show running-config interface show interface switchport show interface capabilities show interface ethernet counters
show interface: show running-config interface EXPLANATION To view the speed and duplex settings of the interfaces in a Cisco switch, you can use one of the following commands: show running-config interface (displays concise summary information) show interface (displays extended information) The show interface capabilities command displays information about the capabilities of the interfaces in the switch, not the current configuration. The show interface ethernet counters command displays statistics for interfaces. The show interface switchport command displays VLAN information about switch interfaces.
Which TCP/IP utility gives you the following output? tracert nslookup ipconfig ifconfig
tracert EXPLANATION The exhibit shows a few lines from the tracert command, which shows you each host a packet must pass through to reach its destination.
Examine the following output: 4 22 ms 21 ms 22 ms sttlwa01gr02.bb.ispxy.com [154.11.10.62]5 39 ms 39 ms 65 ms plalca01gr00.bb.ispxy.com [154.11.12.11]6 39 ms 39 ms 39 ms Rwest.plalca01gr00.bb.ispxy.com [154.11.3.14]7 40 ms 39 ms 46 ms svl-core-03.inet.ispxy.net [205.171.205.29]8 75 ms 117 ms 63 ms dia-core-01.inet.ispxy.net [205.171.142.1] Which of these commands produced this output? nslookup pingroute ping tracert
tracert EXPLANATION The output is from a tracert command run on a Windows Server 2003 system. The tracert command provides information on each step in the route a packet takes to reach a remote host. Responses from each hop on the route are measured three times to provide an accurate representation of how long the packet takes to reach and be returned by that host. This information can be useful for locating congestion points on a network or when verifying that network routing is operating as expected. The ping command is used to test connectivity between devices on a network. Like tracert, ping sends three packets to the target host, but it does not report information on any intermediate devices it traverses to reach the target. nslookup is a tool provided on Linux, Unix, and Windows systems that allows manual name resolution requests to be made to a DNS server. This can be useful when troubleshooting name resolution problems.
You are the network administrator of a branch office of your company. The branch office network is part of a WAN that covers most of the United States. The office has two Windows 2000 servers, two UNIX servers, one Windows NT server, 90 Windows 98 clients, 40 Windows 2000 Professional clients, and five Macintosh clients. Users have been complaining that they are unable to access resources over the WAN at the main headquarters. You suspect that one of the routers between your office and the main headquarters is not working properly. What TCP/IP utility can you use to see if a router is working properly? nslookup netstat nbtstat tracert
tracert EXPLANATION tracert shows you the series of routers that are used between the source and destination computers. If a router is not functioning, tracert can help you find which router is not working by showing you the last router it was able to contact successfully.
