Networking 2

What does a cable rating of "plenum" indicate about the cable?

A plenum-rated cable will not produce toxic gas when it burns; therefore, it can be used in plenum areas, such as ventilation ducts and other areas that carry breathable air. Non-plenum cables are covered with PVC, which produces toxic gas when it burns. Most fire codes require plenum-rated cable in any area that carries breathable air.

Which hardware device operates at the physical layer of the Open Systems Interconnection (OSI) model to connect computers in a network?

A hub is a hardware device that operates at the Physical layer (Layer 1) of the OSI model to connect computers in a network. The OSI model is used to manage network communications. The seven levels of the OSI model are used to describe network protocols and devices. A switch can connect computers in a network, but does not operate at the physical layer of the OSI model. A switch operates at the Data Link layer (Layer 2). A switch enhances network connectivity and performance. It also reduces the network traffic when compared to a hub by forwarding the data packets only to the destination port. A bridge can connect computers in a network, but does not operate at the physical layer of the OSI model. A bridge operates at the Data Link layer (Layer 2). A bridge is a hardware device that connects two portions of a network or two similar networks together. This device is used to reduce network traffic by broadcasting data packets to all the possible destinations within a particular segment. A router can connect computers in a network, but usually connects dissimilar networks to each other. Additionally, a router operates at the Network layer (Layer 3) of the OSI model.

Your network is shown in the following exhibit. (Click the Exhibit(s) button.) Which type of network topology is shown in the exhibit?

A star topology connects all of the nodes, or computers, to a central device such as a hub. The hub has a connection port for each node. This arrangement minimizes the risk of failure of the entire network. For example, if one node on the network fails, only that node will be impacted by the failure. All other nodes on the network will continue to operate. Therefore, a star topology is the easiest to expand. A 100BaseT network uses a physical star topology. A bus topology uses a single cable, also known as a backbone, segment, or trunk, to connect all networked devices. Therefore, a bus topology uses less cabling than other topologies. However, it also means that the entire network will stop responding should a cable failure occur. A ring topology connects every computer to two other computers, forming a physical "ring." In a ring topology, signals generally travel in one direction around the ring as they are passed from one computer to another. If a cable failure occurs, there is a break in the ring, which causes the entire network to stop responding. A mesh topology connects every device to every other device using a series of point-to-point connections. This makes the mesh topology very expensive, but it creates several possible signal paths, providing a high level of fault tolerance. This is important if you cannot afford to have any portion of your network down at any time. A wireless topology typically places computers near or around transceivers, which are known as access points. Another type of network topology that you may see on the A+ exams is a hybrid network. This type of network combines two or more of the other network topologies into a single network. This often occurs when a department has an existing network and then a company decides to implement a network. The company often chooses to leave the existing departmental network in place and incorporate it into the network using the appropriate hardware.

Which of the following is an example of an IPv6 address?

An example of an IPv6 address is fe80::200:f8ff:fe21:67cf. An example of an IPv4 address is 127.0.0.1 and 192.1.0.1. An example of a MAC address, which is hard-coded into the network interface card (NIC) by the manufacturer, is 00-0C-F1-56-98-AD.

Which TCP/IP configuration information must a computer on a network have before it can communicate with the Internet? (Choose three.)

Before any computer on a network can communicate with the Internet, it will need an IP address, a default gateway, and a subnet mask. You can supply this information manually, or you can use a DCHP server to supply this information automatically. The IP address is a 32-digit binary number that is needed to identify each device, or host, on the Internet. The IP address provides a logical address for each device. The subnet mask is used to block out a portion of the IP address. The purpose of the blocking is to distinguish the network ID from the host ID. It is also used to identify whether the IP address of the destination host is on a local network or on a remote network. Subnet mask addresses are 32-bit numbers. Every host on a TCP/IP network will need to be configured with a subnet mask. Use the default subnet mask if you are not dividing your network into subnets. You will need to create custom subnet addresses if your networks are to be divided into subnets. The default gateway is the address of the default router. While you can configure a static IP address, meaning that the IP address is manually entered in the computer's settings, it is considered a best practice to configure the computer to obtain an IP address automatically using Dynamic Host Configuration Protocol (DHCP). Another important part of the IP settings includes configuring the address of the Domain Name System (DNS) server.

Which unshielded twisted pair (UTP) cable supports data transfer up to 100 Mbps?

CAT5 UTP cable supports a data transfer rate of up to 100 Mbps. The CAT5e and CAT6 UTP standards support up to 1000 Mbps at 100-meter segments or 10 Gbps at 55-meter segments. CAT6a supports up to 10 Gbps at 100-meter segments. CAT4 UTP cable supports a data transfer rate of only 20 Mbps. CAT3 UTP cable supports a data transfer rate of only 10 Mbps. CAT2 UTP cable supports a data transfer rate of only 4 Mbps.

Which type of cable can operate at up to 10 gigabits per second (Gbps)?

CAT6 cable can operate at up to 10 Gbps in 55-meter segments. It is often referred to as Gigabit Ethernet. CAT6 UTP standards support up to 1000 Mbps at 100-meter segments. CAT6a supports up to 10 Gbps at 100-meter segments. CAT3 cable can operate at up to 10 megabits per second (Mbps). CAT5 cable can operate at up to 100 Mbps. CAT 5e cable can operate at up to 1 Gbps. CAT5e networks can also be referred to as Gigabit Ethernet, but Gigabit Ethernet is more often used to refer to CAT 6 networks.

Which statement is true concerning DHCP?

Dynamic Host Configuration Protocol (DHCP) is a standards-based networking protocol that is used to automate the assignment of IP addresses to DHCP client devices. DHCP is a client/server protocol that uses two components, one on the server and one on the client. The server-side component stores a pool of available IP addresses. The client-side component requests a TCP/IP configuration from an available DHCP server. Several server operating systems support the DHCP server service, including Windows NT Server, Windows 2000 Server, Windows Server 2003/2008, Novell NetWare 6, and Red Hat Linux 9. Most desktop operating systems support the DHCP client service. Domain Name System (DNS) is a network service that is used to resolve host names to IP addresses. DNS is used extensively on the Internet; for example, DNS can be used to resolve the host name www.verigon.com to that Web server's corresponding IP address. Windows Internet Naming Service (WINS) is a network service that can be used to resolve NetBIOS names to IP addresses. NetBIOS names are also known as Windows computer names. The ipconfig command can be used to verify the IP address of a Windows-based computer.

Which network medium is the least susceptible to EMI or signal capture?

Fiber-optic cable carries its signals in the form of modulated pulses of light. Because fiber-optic cables use light pulses rather than electric signals, it is virtually impossible to intercept the signal on a fiber-optic cable without interrupting it and thus being detected. In addition, fiber-optic cable is not susceptible to electro-magnetic interference (EMI). It can span distances of up to two kilometers, or 2,000 meters (6,562 feet) and transmit data at a rate in excess of 100 Mbps. However, fiber-optic cable is the most expensive type of networking cable. The following table presents a comparison of network media:

Which improvements does IPv6 provide over the current IP addressing scheme? (Choose two.)

IPv6 (version 6) or IPng (next generation) offers the following improvements over IPv4: IP address size will increase from 32 bits to 128 bits. Some of the header fields have been dropped. Version 6 has less rigid length limits and the ability to introduce new options. Packets will indicate particular traffic type. Support will be provided for data integrity and confidentiality. The IPv6 header is 40 fixed bytes and has eight fields of information.

Which properties are true regarding IPv6? (Choose two.)

IPv6 uses 128-bit IP addresses and allows for the use of 340 undecillion addresses. IPv4 uses 32-bit addresses and allows for the use of 4 billion addresses.

Which of the following options is a way to increase security in a wireless network?

Media Access Control (MAC) filtering is a way to increase security in a wireless network. With this filtering, the MAC address of each network interface card (NIC) that attempts to connect to the network is checked. Only MAC addresses that are specifically allowed connection are granted connection. When configuring MAC filtering, you should set up an access control list (ACL). MAC filtering is configured on the wireless access point or wireless router. A service-set identifier (SSID) broadcast actually decreases security in a wireless network. If the SSID is broadcast, any wireless NICs in the proximity can locate the network. If you disable SSID broadcast, you increase the security of your network, and users will have to type in the SSID to connect to the network. War driving is a technique used to discover wireless networks. Once intruders locate your wireless network, they attempt to hack into your system. Rogue access points are wireless access points that have been connected to your network without authorization. This decreases the security of your network. Radio frequency interference (RFI) can cause wireless network problems. It can come from cordless phones, microwaves, and other equipment. For example, if your wireless network is frequently dropping connections, you could have a cordless phone interfering with the wireless access point.

Which device can cause interference with 802.11b 2.4-GHz WLANs?

Microwave ovens can cause interference for 802.11b wireless local area networks (WLANs) that operate in the 2.4-GHz frequency band. Microwave ovens operate at the 2.45-GHz frequency band, and can cause interference when used in areas where 802.11b WLANs are deployed. Cordless phones can also cause interference. Typically these cordless phones use a higher transmitting power than the access points and can create a lot of noise in 802.11b WLANs. To avoid the interference from cordless phones, you can change either the location of access points or the location of the cordless phones. You can use the cordless phones that operate at 900MHz frequency band to avoid interference with 802.11b WLANs. Most medical equipment that uses radio frequencies operates in the 2.4-GHz ISM frequency band. Therefore, when doing a site survey, you must consider the interference by microwave ovens, cordless phones , and other devices that operate in the 2.4-GHz ISM frequency band, and you should plan the positions of the access points according to these devices to avoid interference. Pools of water, trees, and construction materials, such as steel and wood, may absorb the radio frequency signals from 802.11b 2.4-GHz WLANs. Objects with water content should be avoided to prevent signal absorption problems. Cellular phones and cable TV cabling do not cause interference with 802.11b WLANs. Keep in mind that wireless networks can be affected by other wireless devices, metal, and water.

You administer computers on a Microsoft Windows 2003 TCP/IP network. On the network, you want to use a domain name-to-Internet Protocol (IP) address name resolution system that provides a central database on a server to resolve domain names to IP addresses. Which options should you implement on your network?

Of the choices presented, you should use Domain Name System (DNS) for domain name-to-IP address resolution on the network that you administer. DNS provides a centralized database of domain name-to-IP address resolutions on a server or servers that other computers on a network can use for name resolution. On a TCP/IP network that uses DNS, only the database files on the DNS servers must be updated to reflect changes that are made to domain name-to-IP address resolutions. When computers cannot communicate on a network, the ability to ping other computers by address by not but name is an indication of a DNS problem. Client computers can be configured with static DNS server entries or can be configured to obtain the DNS server information from the DHCP server. The client-side DNS could be configured incorrectly if a DNS search results in an error. Domain names can also be resolved to IP addresses by using a HOSTS file. On a network that uses a HOSTS file, that file must exist on each computer on the network to enable domain name-to-IP address resolution. When changes are made that affect domain name-to-IP address resolution, then each HOSTS file must be manually updated. LMHOSTS files and Windows Internet Name Service (WINS) are used to resolve NetBIOS names to IP addresses on Microsoft Windows networks, such as Windows NT 4.0 networks.

Which technology is the SLOWEST?

Of the technologies listed, satellite is the slowest. In most satellite implementations, the maximum upload speed is 300 kilobits per second (Kbps), and the maximum download speed is 2000 Kbps. DSL has a maximum speed of 3 Megabits per second (Mbps). Cable has a maximum speed of 30 Mbps. Fiber has a maximum speed of 1000 Mbps.

Which well-known UDP port does DNS use?

Ports allow more than one service or application to communicate at the same time between computers. The Domain Name System (DNS) service uses port 53 to communicate information between name servers. DNS uses both TCP port 53 and UDP port 53. Administrators can assign additional ports for communication on an intranet and through the Internet. There are a total of 65,536 ports from which to choose. Of these, only 1,024 ports are considered well known and, therefore, reserved for a particular service. Port 80 is used by Hypertext Transfer Protocol (HTTP) for browsing the World Wide Web. Port 110 is used by Post Office Protocol Version 3 (POP3) for e-mail. Port 161 is used by Simple Network Management Protocol (SNMP) for network diagnostics.

What is the purpose of PoE?

Power over Ethernet (PoE) allows an Ethernet connection to be used as both a network and power connection. Network-attached storage (NAS) provides a file storage solution that is attached to the network. This is a network or Internet appliance that does not include a monitor, keyboard, or mouse. Network Address Translation (NAT) allows a network of computers to appear to the Internet as a single entity. Trusted Platform Module (TPM) provides a cryptographic hardware platform for securely storing data.

Which of the following statements is true regarding RG6 coaxial cable?

RG6 coaxial cable is thicker than RG59 coaxial cable. None of the other statements is true regarding RG6 coaxial cable. RG6 cable should be used in situations that require the 50-MHz frequencies or higher. RG6 signal quality is better than the signal quality of RG59 cable. RG6 cable has a foil shield. RG59 cable should be used in situations that require lower frequencies than 50 MHz. RG59 is thinner than RG6 cable. RG59 does NOT have a foil shield. For both of these cable types, the maximum cable length is 185 meters, and the maximum transmission speed is 10 Megabits per second (Mbps).

Multimeters have various settings to aid you in isolating problems. Which multimeter check is always performed with the power to the system turned off?

Resistance and continuity checks are always performed with the system power off. Failure to remove the power while conducting these tests can result in damage to the multimeter and the technician performing the test. Resistance is measured in ohms, and is useful when checking fuses, cables, connections, and the system speaker.

Which is the following is a valid Automatic Private IP Addressing (APIPA) address?

The 169.254.2.120 address is a valid APIPA address. By default, Windows XP and Windows 7 client computers are configured to use an APIPA address if the DHCP server does down. The addresses in the APIPA range are 169.254.0.0 through 169.254.255.255. These addresses are not routable and are therefore only usable on the local subnet. The other addresses are all part of the three private IP address ranges, as shown below: 10.0.0.0 through 10.255.255.255 172.16.0.0 through 172.31.255.255 192.168.0.0 through 192.168.255.255 To prevent the use of APIPA addresses, you should change the default settings on the Alternate Configuration tab of the Internet Protocol Version 4 Properties dialog box. On this tab, you can specifically configure a static IP address that the computer should use if the DHCP server is unavailable.

Which cable connector is used in a 1000BaseT network?

The RJ-45 cable connector is used in a gigabit Ethernet or 1000BaseT network. The RJ-45 connector is used with unshielded twisted-pair (UTP) copper-wire cabling and can be used to carry data at up to 1,000 Mbps, which is 1 gigabit per second (Gbps). The SC, ST, and MTRJ connectors are used with fiber-optic cabling. For instance, these cable connectors can be used in a 100BaseFX network. An RJ-11 connector is used to connect telephone cable to a computer modem. While an RJ-11 connector looks similar to an RJ-45 connector, the RJ-11 connector is narrower than an RJ-45 connector because it uses fewer wires.

Which components are displayed in the Wireless Network Connection Status dialog box on a Windows XP-based client computer that is connected to a wireless network? (Choose all that apply.)

The Wireless Network Connection Status dialog box in a Windows XP-based client computer that is connected to a wireless network displays the speed and signal strength of the wireless connection. To open this dialog-box, you can double-click on the wireless networking icon on the Taskbar. The Wireless Network Connection Status dialog-box also displays the status and duration of wireless connection. The Wireless Network Connection Status dialog box in a Windows XP-based client computer that is connected to a wireless network does not display the EAP type or the option to enable or disable IEEE 802.1x authentication. The EAP type and the option to enable or disable IEEE 802.1x authentication are displayed in the Wireless Network Properties dialog box.

Which address is a MAC address?

The address AD-4F-C1-A9-12-CB is a media access control (MAC) address. A MAC address is assigned to each network interface card (NIC). A MAC address is a 12-digit hexadecimal number. Each pair of hexadecimal numbers is referred to as an octet, and the octets are usually separated by dash (-) characters when a MAC address is represented in text. The first three octets in a MAC address identify the NIC manufacturer, and the last three octets act as a serial number to identify the individual NIC. The address 124.24.0.2 is an Internet Protocol version 4 (IPv4) address. An IPv4 address consists of four 8-digit binary numbers, or octets, separated by periods. A decimal number between 0 and 255 inclusive represents each octet in an IPv4 address. The address 00120193:06F1A345CA11 is an Internetwork Packet Exchange (IPX) address. The six digits before the colon (:) character represent the IPX network address, and the last 12 digits after the colon character represent the node address, which is derived from the MAC address of the NIC. The addresses 1234:EF14:45:ADD1:EA23:222:1290:A, 122A::ABCA:0:0:2100, and ACA1:1345:1::123.23.0.1 are IP version 6 (IPv6) addresses. An IPv6 address is a 128-bit number. The preferred representation of an IPv6 address contains eight sections of hexadecimal numbers. Each section is separated from the other sections by a colon, as in the address 1234:EF14:45:ADD1:EA23:222:1290:A. Each section contains up to four numbers, but leading zeros in each section do not need to be represented. For example, the last section of the IPv6 address 1234:EF14:45:ADD1:EA23:222:1290:A is actually :000A. The IPv6 address 122A::ABCA:0:0:2100 is a compressed format IPv6 address. In a compressed format address, the double colon (::) symbol represents complete sections of zeros. Only one double colon character can appear in a compressed IPv6 address. For example, the IPv6 compressed address 122A::ABCA:0:0:2100 is actually 122A:0:0:0:ABCA:0:0:2100 in uncompressed format. The IPv6 address ACA1:1345:1::123.23.0.1 is a mixed IPv6 address that is designed to support IPv4 addressing. The first six sections of a mixed IPv6 address are written in the hexadecimal notation common to IPv6 addresses. The last four sections of the mixed IPv6 address are a dotted-decimal representation of an IPv4 address. In this example, 123.23.0.1 is the dotted-decimal IPv4 portion of the IPv6 mixed address. Note that this address is also compressed. The address AD-4F-C1-A9-12-CB is a media access control (MAC) address. A MAC address is assigned to each network interface card (NIC). A MAC address is a 12-digit hexadecimal number. Each pair of hexadecimal numbers is referred to as an octet, and the octets are usually separated by dash (-) characters when a MAC address is represented in text. The first three octets in a MAC address identify the NIC manufacturer, and the last three octets act as a serial number to identify the individual NIC. The address 124.24.0.2 is an Internet Protocol version 4 (IPv4) address. An IPv4 address consists of four 8-digit binary numbers, or octets, separated by periods. A decimal number between 0 and 255 inclusive represents each octet in an IPv4 address. The address 00120193:06F1A345CA11 is an Internetwork Packet Exchange (IPX) address. The six digits before the colon (:) character represent the IPX network address, and the last 12 digits after the colon character represent the node address, which is derived from the MAC address of the NIC. The addresses 1234:EF14:45:ADD1:EA23:222:1290:A, 122A::ABCA:0:0:2100, and ACA1:1345:1::123.23.0.1 are IP version 6 (IPv6) addresses. An IPv6 address is a 128-bit number. The preferred representation of an IPv6 address contains eight sections of hexadecimal numbers. Each section is separated from the other sections by a colon, as in the address 1234:EF14:45:ADD1:EA23:222:1290:A. Each section contains up to four numbers, but leading zeros in each section do not need to be represented. For example, the last section of the IPv6 address 1234:EF14:45:ADD1:EA23:222:1290:A is actually :000A. The IPv6 address 122A::ABCA:0:0:2100 is a compressed format IPv6 address. In a compressed format address, the double colon (::) symbol represents complete sections of zeros. Only one double colon character can appear in a compressed IPv6 address. For example, the IPv6 compressed address 122A::ABCA:0:0:2100 is actually 122A:0:0:0:ABCA:0:0:2100 in uncompressed format. The IPv6 address ACA1:1345:1::123.23.0.1 is a mixed IPv6 address that is designed to support IPv4 addressing. The first six sections of a mixed IPv6 address are written in the hexadecimal notation common to IPv6 addresses. The last four sections of the mixed IPv6 address are a dotted-decimal representation of an IPv4 address. In this example, 123.23.0.1 is the dotted-decimal IPv4 portion of the IPv6 mixed address. Note that this address is also compressed. The address AD-4F-C1-A9-12-CB is a media access control (MAC) address. A MAC address is assigned to each network interface card (NIC). A MAC address is a 12-digit hexadecimal number. Each pair of hexadecimal numbers is referred to as an octet, and the octets are usually separated by dash (-) characters when a MAC address is represented in text. The first three octets in a MAC address identify the NIC manufacturer, and the last three octets act as a serial number to identify the individual NIC. The address 124.24.0.2 is an Internet Protocol version 4 (IPv4) address. An IPv4 address consists of four 8-digit binary numbers, or octets, separated by periods. A decimal number between 0 and 255 inclusive represents each octet in an IPv4 address. The address 00120193:06F1A345CA11 is an Internetwork Packet Exchange (IPX) address. The six digits before the colon (:) character represent the IPX network address, and the last 12 digits after the colon character represent the node address, which is derived from the MAC address of the NIC. The addresses 1234:EF14:45:ADD1:EA23:222:1290:A, 122A::ABCA:0:0:2100, and ACA1:1345:1::123.23.0.1 are IP version 6 (IPv6) addresses. An IPv6 address is a 128-bit number. The preferred representation of an IPv6 address contains eight sections of hexadecimal numbers. Each section is separated from the other sections by a colon, as in the address 1234:EF14:45:ADD1:EA23:222:1290:A. Each section contains up to four numbers, but leading zeros in each section do not need to be represented. For example, the last section of the IPv6 address 1234:EF14:45:ADD1:EA23:222:1290:A is actually :000A. The IPv6 address 122A::ABCA:0:0:2100 is a compressed format IPv6 address. In a compressed format address, the double colon (::) symbol represents complete sections of zeros. Only one double colon character can appear in a compressed IPv6 address. For example, the IPv6 compressed address 122A::ABCA:0:0:2100 is actually 122A:0:0:0:ABCA:0:0:2100 in uncompressed format. The IPv6 address ACA1:1345:1::123.23.0.1 is a mixed IPv6 address that is designed to support IPv4 addressing. The first six sections of a mixed IPv6 address are written in the hexadecimal notation common to IPv6 addresses. The last four sections of the mixed IPv6 address are a dotted-decimal representation of an IPv4 address. In this example, 123.23.0.1 is the dotted-decimal IPv4 portion of the IPv6 mixed address. Note that this address is also compressed. The address AD-4F-C1-A9-12-CB is a media access control (MAC) address. A MAC address is assigned to each network interface card (NIC). A MAC address is a 12-digit hexadecimal number. Each pair of hexadecimal numbers is referred to as an octet, and the octets are usually separated by dash (-) characters when a MAC address is represented in text. The first three octets in a MAC address identify the NIC manufacturer, and the last three octets act as a serial number to identify the individual NIC. The address 124.24.0.2 is an Internet Protocol version 4 (IPv4) address. An IPv4 address consists of four 8-digit binary numbers, or octets, separated by periods. A decimal number between 0 and 255 inclusive represents each octet in an IPv4 address. The address 00120193:06F1A345CA11 is an Internetwork Packet Exchange (IPX) address. The six digits before the colon (:) character represent the IPX network address, and the last 12 digits after the colon character represent the node address, which is derived from the MAC address of the NIC. The addresses 1234:EF14:45:ADD1:EA23:222:1290:A, 122A::ABCA:0:0:2100, and ACA1:1345:1::123.23.0.1 are IP version 6 (IPv6) addresses. An IPv6 address is a 128-bit number. The preferred representation of an IPv6 address contains eight sections of hexadecimal numbers. Each section is separated from the other sections by a colon, as in the address 1234:EF14:45:ADD1:EA23:222:1290:A. Each section contains up to four numbers, but leading zeros in each section do not need to be represented. For example, the last section of the IPv6 address 1234:EF14:45:ADD1:EA23:222:1290:A is actually :000A. The IPv6 address 122A::ABCA:0:0:2100 is a compressed format IPv6 address. In a compressed format address, the double colon (::) symbol represents complete sections of zeros. Only one double colon character can appear in a compressed IPv6 address. For example, the IPv6 compressed address 122A::ABCA:0:0:2100 is actually 122A:0:0:0:ABCA:0:0:2100 in uncompressed format. The IPv6 address ACA1:1345:1::123.23.0.1 is a mixed IPv6 address that is designed to support IPv4 addressing. The first six sections of a mixed IPv6 address are written in the hexadecimal notation common to IPv6 addresses. The last four sections of the mixed IPv6 address are a dotted-decimal representation of an IPv4 address. In this example, 123.23.0.1 is the dotted-decimal IPv4 portion of the IPv6 mixed address. Note that this address is also compressed. The address AD-4F-C1-A9-12-CB is a media access control (MAC) address. A MAC address is assigned to each network interface card (NIC). A MAC address is a 12-digit hexadecimal number. Each pair of hexadecimal numbers is referred to as an octet, and the octets are usually separated by dash (-) characters when a MAC address is represented in text. The first three octets in a MAC address identify the NIC manufacturer, and the last three octets act as a serial number to identify the individual NIC. The address 124.24.0.2 is an Internet Protocol version 4 (IPv4) address. An IPv4 address consists of four 8-digit binary numbers, or octets, separated by periods. A decimal number between 0 and 255 inclusive represents each octet in an IPv4 address. The address 00120193:06F1A345CA11 is an Internetwork Packet Exchange (IPX) address. The six digits before the colon (:) character represent the IPX network address, and the last 12 digits after the colon character represent the node address, which is derived from the MAC address of the NIC. The addresses 1234:EF14:45:ADD1:EA23:222:1290:A, 122A::ABCA:0:0:2100, and ACA1:1345:1::123.23.0.1 are IP version 6 (IPv6) addresses. An IPv6 address is a 128-bit number. The preferred representation of an IPv6 address contains eight sections of hexadecimal numbers. Each section is separated from the other sections by a colon, as in the address 1234:EF14:45:ADD1:EA23:222:1290:A. Each section contains up to four numbers, but leading zeros in each section do not need to be represented. For example, the last section of the IPv6 address 1234:EF14:45:ADD1:EA23:222:1290:A is actually :000A. The IPv6 address 122A::ABCA:0:0:2100 is a compressed format IPv6 address. In a compressed format address, the double colon (::) symbol represents complete sections of zeros. Only one double colon character can appear in a compressed IPv6 address. For example, the IPv6 compressed address 122A::ABCA:0:0:2100 is actually 122A:0:0:0:ABCA:0:0:2100 in uncompressed format. The IPv6 address ACA1:1345:1::123.23.0.1 is a mixed IPv6 address that is designed to support IPv4 addressing. The first six sections of a mixed IPv6 address are written in the hexadecimal notation common to IPv6 addresses. The last four sections of the mixed IPv6 address are a dotted-decimal representation of an IPv4 address. In this example, 123.23.0.1 is the dotted-decimal IPv4 portion of the IPv6 mixed address. Note that this address is also compressed. The address AD-4F-C1-A9-12-CB is a media access control (MAC) address. A MAC address is assigned to each network interface card (NIC). A MAC address is a 12-digit hexadecimal number. Each pair of hexadecimal numbers is referred to as an octet, and the octets are usually separated by dash (-) characters when a MAC address is represented in text. The first three octets in a MAC address identify the NIC manufacturer, and the last three octets act as a serial number to identify the individual NIC. The address 124.24.0.2 is an Internet Protocol version 4 (IPv4) address. An IPv4 address consists of four 8-digit binary numbers, or octets, separated by periods. A decimal number between 0 and 255 inclusive represents each octet in an IPv4 address. The address 00120193:06F1A345CA11 is an Internetwork Packet Exchange (IPX) address. The six digits before the colon (:) character represent the IPX network address, and the last 12 digits after the colon character represent the node address, which is derived from the MAC address of the NIC. The addresses 1234:EF14:45:ADD1:EA23:222:1290:A, 122A::ABCA:0:0:2100, and ACA1:1345:1::123.23.0.1 are IP version 6 (IPv6) addresses. An IPv6 address is a 128-bit number. The preferred representation of an IPv6 address contains eight sections of hexadecimal numbers. Each section is separated from the other sections by a colon, as in the address 1234:EF14:45:ADD1:EA23:222:1290:A. Each section contains up to four numbers, but leading zeros in each section do not need to be represented. For example, the last section of the IPv6 address 1234:EF14:45:ADD1:EA23:222:1290:A is actually :000A. The IPv6 address 122A::ABCA:0:0:2100 is a compressed format IPv6 address. In a compressed format address, the double colon (::) symbol represents complete sections of zeros. Only one double colon character can appear in a compressed IPv6 address. For example, the IPv6 compressed address 122A::ABCA:0:0:2100 is actually 122A:0:0:0:ABCA:0:0:2100 in uncompressed format. The IPv6 address ACA1:1345:1::123.23.0.1 is a mixed IPv6 address that is designed to support IPv4 addressing. The first six sections of a mixed IPv6 address are written in the hexadecimal notation common to IPv6 addresses. The last four sections of the mixed IPv6 address are a dotted-decimal representation of an IPv4 address. In this example, 123.23.0.1 is the dotted-decimal IPv4 portion of the IPv6 mixed address. Note that this address is also compressed. The address AD-4F-C1-A9-12-CB is a media access control (MAC) address. A MAC address is assigned to each network interface card (NIC). A MAC address is a 12-digit hexadecimal number. Each pair of hexadecimal numbers is referred to as an octet, and the octets are usually separated by dash (-) characters when a MAC address is represented in text. The first three octets in a MAC address identify the NIC manufacturer, and the last three octets act as a serial number to identify the individual NIC. The address 124.24.0.2 is an Internet Protocol version 4 (IPv4) address. An IPv4 address consists of four 8-digit binary numbers, or octets, separated by periods. A decimal number between 0 and 255 inclusive represents each octet in an IPv4 address. The address 00120193:06F1A345CA11 is an Internetwork Packet Exchange (IPX) address. The six digits before the colon (:) character represent the IPX network address, and the last 12 digits after the colon character represent the node address, which is derived from the MAC address of the NIC. The addresses 1234:EF14:45:ADD1:EA23:222:1290:A, 122A::ABCA:0:0:2100, and ACA1:1345:1::123.23.0.1 are IP version 6 (IPv6) addresses. An IPv6 address is a 128-bit number. The preferred representation of an IPv6 address contains eight sections of hexadecimal numbers. Each section is separated from the other sections by a colon, as in the address 1234:EF14:45:ADD1:EA23:222:1290:A. Each section contains up to four numbers, but leading zeros in each section do not need to be represented. For example, the last section of the IPv6 address 1234:EF14:45:ADD1:EA23:222:1290:A is actually :000A. The IPv6 address 122A::ABCA:0:0:2100 is a compressed format IPv6 address. In a compressed format address, the double colon (::) symbol represents complete sections of zeros. Only one double colon character can appear in a compressed IPv6 address. For example, the IPv6 compressed address 122A::ABCA:0:0:2100 is actually 122A:0:0:0:ABCA:0:0:2100 in uncompressed format. The IPv6 address ACA1:1345:1::123.23.0.1 is a mixed IPv6 address that is designed to support IPv4 addressing. The first six sections of a mixed IPv6 address are written in the hexadecimal notation common to IPv6 addresses. The last four sections of the mixed IPv6 address are a dotted-decimal representation of an IPv4 address. In this example, 123.23.0.1 is the dotted-decimal IPv4 portion of the IPv6 mixed address. Note that this address is also compressed. The address AD-4F-C1-A9-12-CB is a media access control (MAC) address. A MAC address is assigned to each network interface card (NIC). A MAC address is a 12-digit hexadecimal number. Each pair of hexadecimal numbers is referred to as an octet, and the octets are usually separated by dash (-) characters when a MAC address is represented in text. The first three octets in a MAC address identify the NIC manufacturer, and the last three octets act as a serial number to identify the individual NIC. The address 124.24.0.2 is an Internet Protocol version 4 (IPv4) address. An IPv4 address consists of four 8-digit binary numbers, or octets, separated by periods. A decimal number between 0 and 255 inclusive represents each octet in an IPv4 address. The address 00120193:06F1A345CA11 is an Internetwork Packet Exchange (IPX) address. The six digits before the colon (:) character represent the IPX network address, and the last 12 digits after the colon character represent the node address, which is derived from the MAC address of the NIC. The addresses 1234:EF14:45:ADD1:EA23:222:1290:A, 122A::ABCA:0:0:2100, and ACA1:1345:1::123.23.0.1 are IP version 6 (IPv6) addresses. An IPv6 address is a 128-bit number. The preferred representation of an IPv6 address contains eight sections of hexadecimal numbers. Each section is separated from the other sections by a colon, as in the address 1234:EF14:45:ADD1:EA23:222:1290:A. Each section contains up to four numbers, but leading zeros in each section do not need to be represented. For example, the last section of the IPv6 address 1234:EF14:45:ADD1:EA23:222:1290:A is actually :000A. The IPv6 address 122A::ABCA:0:0:2100 is a compressed format IPv6 address. In a compressed format address, the double colon (::) symbol represents complete sections of zeros. Only one double colon character can appear in a compressed IPv6 address. For example, the IPv6 compressed address 122A::ABCA:0:0:2100 is actually 122A:0:0:0:ABCA:0:0:2100 in uncompressed format. The IPv6 address ACA1:1345:1::123.23.0.1 is a mixed IPv6 address that is designed to support IPv4 addressing. The first six sections of a mixed IPv6 address are written in the hexadecimal notation common to IPv6 addresses. The last four sections of the mixed IPv6 address are a dotted-decimal representation of an IPv4 address. In this example, 123.23.0.1 is the dotted-decimal IPv4 portion of the IPv6 mixed address. Note that this address is also compressed.

Match the frequency and speed characteristics on the left to the wireless specification on the right. Move the correct items from the left column to the column on the right to match the characteristics with the correct specification.

The characteristics match with the 802.11 specifications as follows: 802.11a - 5 GHz, up to 54 Mbps 802.11b - 2.4 GHz, up to 11 Mbps 802.11g - 2.4 GHz, up to 54 Mbps 802.11n - 2.4 or 5 GHz, up to 600 Mbps 802.11g devices are backwards compatible with 802.11b devices.

Which tool would be used to measure the voltage supplied by a disk drive power connector?

The multimeter is a versatile test instrument that is used to measure values of voltage, current, and resistance associated with electrical circuits. A multimeter combines three tools in one. It includes a volt meter, an ohm meter, and an am meter. In this scenario, the voltage of a disk drive power connector would be measured with the multimeter set to read volts of direct current (VDC). Electricity that always moves in one direction is referred to as direct current, and electricity that reverses direction regularly is referred to as alternating current. The voltage at an outlet is measured as volts of alternating current (VAC). A multimeter set to read volts of direct current but connected to alternating current, or set to read volts of alternating current but connected to direct current, will usually give a reading of 0 volts. A volt is a type of force known as electromotive force. Voltage can be measured even when no current is moving; this is analogous to water pressure that is present at a valve even when no water is flowing. Multimeters can be set to measure electrical resistance. Electrical resistance is measured in units of ohms, which are abbreviated either by the Roman letter O or by the Greek letter omega. A multimeter that measures volts and ohms is sometimes referred to as a VOM, for volt-ohm meter, or as a DVOM for digital volt-ohm meter. The primary difference between a VOM and a DVOM is that a VOM has a meter equipped with a moving needle, and a DVOM has a digital display that shows numbers and units. Usually, multimeters can also measure electric current, typically in units of milliamperes (mA). A milliampere, or milliamp, is one thousandth of an ampere (A) and can be represented as 1 mA or as 0.001 A. An ohmmeter is an instrument that measures electrical resistance only, usually with more accuracy than the ohm scale on a multimeter. A Small Computer System Interface (SCSI) terminator is a resistor that is placed at the end of a SCSI chain to prevent the reflection of data signals back down the chain. The Windows Resource Meter is a software application in Microsoft Windows 9x operating systems that can be used to monitor the percent utilization of system resources, user resources, and graphics device interface (GDI) resources; the Resource Meter cannot be used to measure voltage.

Which type of address does a hardware vendor assign?

The physical device, or hardware, address is also referred to as the Media Access Control (MAC) address. A MAC address is a unique number that is assigned to a network interface card (NIC) when the card is manufactured. No two computers on a network can have the same MAC address. The Data Link layer of the OSI model uses these addresses to communicate between devices on local network segments. Although these addresses are considered permanently assigned, some protocols enable them to be changed. An example of a MAC address is 00-AA-00-62-A1-09.

Match the protocol from the left with the default port it uses on the right. Move the correct items from the left column to the column on the right to match the protocol with the correct default port.

The protocols given use these default ports: Port 20 - FTP Port 23 - Telnet Port 25 - SMTP Port 53 - DNS Port 80 - HTTP FTP also uses port 21, but it was not listed in this scenario.

Match the tools on the left to the descriptions on the right. Move the correct items from the left column to the column on the right to match the tools with the descriptions.

The tools and descriptions are as follows: Cable tester - Verifies that a cable is good Crimper - Attaches media connectors to the ends of the cable Loopback plug - Echoes signals over a port to ensure it is working properly Multimeter - Includes a voltmeter, an ohmmeter, and an ammeter to measure voltage, current, and resistance, respectively Punchdown tool - Attaches cable to a patch panel Toner probe - Includes a tone generator and a tone locater to locate the ends of a cable

For what purpose have IP addresses in the 192.168.0.0 through 192.168.255.255 range been reserved?

There are three blocks of IP addresses that have been reserved by the Internet Assigned Numbers Authority (IANA) for private networks. These addresses can be used for IP addressing on a private network that does not need to be connected to the Internet. The three blocks of addresses are listed below: 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 A computer using a private IP address cannot directly communicate with the Internet. The only way Internet communication can occur with a computer that uses an IP address in the private network range is through a proxy server.

You need to view the Media Access Control (MAC) address for your Windows XP computer's wireless network connection. You navigate to the Wireless Network Configuration Status page. Which button should you click?

To view the MAC address for your Windows XP computer's wireless network connection, you should click the Details button on the Support tab of the Wireless Network Configuration Status page. The Properties button on the General tab displays the protocols and drivers used by the wireless connection. The View Wireless Network button on the General tab displays the available wireless networks. The Repair button on the Support tab is used to repair the connection, including releasing and renewing a leased IP address.

Which multimeter setting should you use to test a computer's power supply output?

Use the DC voltage setting on your multimeter when testing the output of any power-supply connector. The power supply converts the AC power from the wall outlet into DC power levels that the computer can safely use. When testing the power output of a power supply, you should test the disk drive power supply and the motherboard power supply. The power that you should expect to find on each pin of the motherboard connector depends on the form factor (such as Baby AT and ATX). The form factor refers to the physical size and shape of a device, such as a motherboard. Disk drive power-supply connectors are standard across the industry. They have four pins, which have the following characteristics: Pin 1 - Yellow wire (+12 VDC) Pin 2 - Black wire (Ground) Pin 3 - Black wire (Ground) Pin 4 - Red wire (+5 VDC)

You use a computer named Wkst1 on a TCP/IP network, which is installed with an application that uses UDP to send a file from your computer to a computer named Wkst2. Data collisions occur, and several data packets are lost during transmission.

User Datagram Protocol (UDP) is a connectionless protocol; thus, it will drop the packets and it will not automatically retransmit them. Because an application is not typically responsible for transmitting data packets across a network, the application in this scenario cannot drop the packets. Instead, an application that uses UDP will usually detect that UDP has dropped packets, and the application will retransmit any dropped packets. Other connectionless protocols, such as IP and Internetwork Packet Exchange (IPX), function similarly to UDP. For example, if the application in this scenario were using IPX to transmit data, then IPX would drop the lost packets and the application would retransmit the dropped packets. A connection-oriented protocol, such as TCP or Sequenced Packet Exchange (SPX), will automatically retransmit dropped packets without the intervention of a higher-level protocol or application.

You want to set up a wireless network with data throughput of 54 Mbps. Which two wireless specifications will provide a data throughput of 54 Mbps? (Choose two.)

You can use either the 802.11a or the 802.11g specifications. Both 802.11a and 802.11g provide data throughput of 54 Mbps. The 802.11g wireless network standard provides backward compatibility with the 802.11b wireless network specification, but the 802.11a network specification does not provide backward compatibility to any other wireless network because it operates in the 5 GHz frequency range, rather than the 2.4 GHz range that 802.11b and 802.1g operate in. You should not use the 802.11b wireless network specification. The 802.11b network specification provides data throughput of only 11 Mbps. You should not use the 802.11 wireless network specification. The 802.11 provides data throughput of only 2 Mbps. The 802.11n wireless standard uses the 2.4 or 5.0 GHz range and is reported to be capable of up to 600 Mbps. However, 300 to 400 Mbps is usually the maximum in most of today's deployments.

What is the minimum category of UTP cable used with 10BaseT?

10BaseT requires a minimum of Category 3 cable. Category 3 cable is acceptable for 10-Mbps transmissions but has largely been phased out in favor of the newer Category 5e and Category 6 standards. These newer cables are rated for much faster speeds (1000 Mbps) and provide backwards compatibility with the older, and much slower 10-Mbps standards. Most cable suppliers no longer manufacture Category 3 cable. Category 2 cable is not suitable for 10-Mbps transmissions. It only supports speeds of up to 4 Mbps. Category 5 is suitable for transmissions of up to 100 Mbps. It has been phased out in favor of Category 5e and Category 6, which support speeds of up to 1000 Mbps. While Category 5e supports speeds of up to 1000 Mbps, Category 6 is recommend for best results.

What is the maximum segment distance for data transmission using 10BaseT, 100BaseT, and 1000BaseT?

10BaseT, 100BaseT, and 1000BaseT Ethernet use unshielded twisted-pair cable (UTP) as their transmission medium. The maximum transmission distance of UTP cable is 100 meters, or 328 feet. This distance can be increased using repeaters.

You need to implement a network among nine computers in one large office. There is no cabling installed in the building, so the cabling needs to be purchased. Which network topology would require you to purchase the least amount of cabling?

A bus topology uses a single cable and all network devices connect to that single backbone. Because devices connect to a single cable, this topology typically requires the least amount of cabling. However, should that single cable fail, the entire network would stop responding. The following table lists the advantages and disadvantages of the different network topologies:

Your network is shown in the following exhibit. (Click the Exhibit(s) button.) Which type of network is shown in the exhibit?

A bus topology uses a single cable, also known as a backbone, segment, or trunk, to connect all networked devices. Therefore, a bus topology uses less cabling than other topologies. However, it also means that the entire network will stop responding should a cable failure occur. A star topology connects all of the nodes, or computers, to a central device such as a hub. The hub has a connection port for each node. This arrangement minimizes the risk of failure of the entire network. For example, if a break occurs on the network, only that node will be impacted by the failure. All other nodes on the network will continue to operate. A ring topology connects every computer to two other computers, forming a physical "ring." In a ring topology, signals generally travel in one direction around the ring as they are passed from one computer to another. If a cable failure occurs, there is a break in the ring, which causes the entire network to stop responding. A mesh topology connects every device to every other device using a series of point-to-point connections. This makes the mesh topology very expensive, but it creates several possible signal paths, providing a high level of fault tolerance. This is important if you cannot afford to have any portion of your network down at any time. A wireless topology typically places computers near or around transceivers, known as access points. Another type of network topology that you may see on the A+ exams is a hybrid network. This type of network combines two or more of the other network topologies into a single network. This often occurs when a department has an existing network and then a company decides to implement a network. The company often chooses to leave the existing departmental network in place and incorporate it into the network using the appropriate hardware.

Which term is most commonly used to describe equipment that creates a demilitarized zone (DMZ)?

A firewall is used to create a demilitarized zone (DMZ). A DMZ is a zone located between a company's internal network and the Internet that usually contains servers that the public will be accessing. The DMZ implementation provides an extra security precaution to protect the resources on the company's internal network. Usually two firewalls are used to create a DMZ. One firewall resides between the public network and DMZ, and another firewall resides between the DMZ and private network. A router is used to create individual subnetworks on an Ethernet network. Routers operate at the Network layer of the OSI model. While a firewall can also be a router, it is referred to as a firewall when it functions to create a DMZ. An active hub is used to connect devices in a star topology. An active hub has circuitry that allows signal regeneration. A passive hub connects devices in a star topology, but it does not provide any signal regeneration. A firewall is classified as a rule-based access control device. Rules are configured on the firewall to allow or deny packet passage from one network to another. The configuration of the rules is one of the biggest concerns for a firewall, because the rules can be very complex. Misconfiguration can easily lead to security breaches. Filters are created according to the company's security policy. To provide maximum file security, firewalls should not run the Network Information System (NIS) file system. Compilers should be deleted from firewalls.

Which hardware device supports protocol translation between dissimilar systems at different Open Systems Interconnection (OSI) layers?

A gateway supports protocol translation between dissimilar networks at different OSI layers. For example, a gateway would be used to connect an Ethernet network with an IBM network. Though a router can also connect dissimilar networks, it works only at one layer of the OSI model. You can use a hub to connect multiple computers in a network. Hubs operate strictly at Layer 1 (the physical layer) of the OSI model. By default, they operate in half-duplex mode. A switch connects multiple computers in a network. By default, switches operate in full-duplex mode. A switch is the best device to use to replace a hub. Keep in mind the main difference between hubs and switches. Hubs broadcast packets to all ports on the hub. Switches send a packet only to the port on which the destination address resides. Because switches do not allow data broadcasts, they prevent data collisions. The main difference between a switch and a router is that a switch interconnects devices on the same network, where a router interconnects one or more networks.

Which cable uses a light-emitting diode (LED)?

A multi-mode fiber optic cable uses an LED to emit the light from the current that passes through the LED. An LED uses two semiconductors: p-type semiconductors and n-type semiconductors. When both the semiconductors are kept in direct contact, they form a region called P-N junction. The current is passed from the p-type semiconductor to the n-type semiconductor and light emits from the current. The LED is used in fiber optics for faster data transmission that occurs in remote controls and LCD backlighting. Coaxial cable does not use an LED. Coaxial cable is half-duplex and supports a speed of 10 Mbps. Coaxial-RG-8 cables are used in the 10Base5 network. Unshielded twisted pair (UTP) cable does not use an LED. UTP cable is used in the 1000BaseT network. The UTP cable contains four pairs of twisted cables. The UTP cables are in pairs in the unshielded form. A shielded twisted pair (STP) cable does not use an LED. The STP cable is used in the 1000BaseCX network. The STP cable contains four pairs of twisted cables. Each twisted pair is wrapped in a foil that protects them from any kind of interference. Single-mode fiber optic cable uses a laser diode to emit the light. Laser diodes produce the type of light required to travel down the single-mode fiber cable. The light produced must be an in-phase, single-frequency, and unidirectional light ray.

Which Internet connection has a line-of-sight requirement?

A satellite connection has a line-of-sight requirement between the dish and the satellite. Satellite Internet connections are popular in rural areas where other high-speed Internet connections are not available. Dial-up, DSL, and cable Internet connections do not have line-of-sight requirements. A dial-up connection uses a phone line to connect the computer to the Internet Service Provider (ISP). The phone line connects to the computer via a modem. A DSL connection uses a DSL line to connect the computer to the ISP via a DSL modem. A cable connection uses a cable provider's cable line to connect the computer to the ISP via a cable modem. Satellite, DSL, and cable connections are always on. A dial-up connection has to be initiated. There is a type of wireless Internet service that includes a line-of-sight requirement. This Internet access usually operates at a higher speed than satellite connections. Worldwide Interoperability for Microwave Access (WiMAX) and 3G Long Term Evolution (LTE) are two cellular technologies. Knowledge of WiMAX is required for the A+ certification. It offers 10 Mbps. The line-of-sight version of WiMAX uses fixed antennas that point directly to a WiMAX transceiver. Non-line-of-sight WiMAX uses base stations. The maximum range for WiMAX is 30 miles.

Which hardware device operates at the data-link layer of the Open Systems Interconnection (OSI) model and ensures that data is delivered only to the destination port?

A switch operates at the Data Link layer (Layer 2) of the OSI model and provides network connectivity to computers connected to the switch. A switch enhances the network connectivity and performance to reduce the network traffic by forwarding the data packets only to the destination port. A hub is a hardware device that operates at the Physical layer (Layer 1) of the OSI model and provides network connectivity to computers connected to a hub. A bridge is a hardware device that connects two portions of a network or two similar networks. A bridge also operates at the Data Link layer (Layer 2) of the OSI model, but it broadcasts data packets to all the possible destinations within a particular segment. A router is a hardware device that transmits data among computers in different networks. A router operates at the Network layer (Layer 3) of the OSI model. If you create a test network of several computers and any one of these devices, you should ensure that the cables are properly routed, especially if the cables must cross aisles. You should keep tripping hazards forefront in any routing considerations.

Which network type uses WEP for security?

An 802.11b wireless network uses WEP security technology. According to the published IEEE 802.11 standard, the acronym WEP stands for Wired Equivalent Privacy, but many variations can be found, such as Wireless Encryption Protocol. The concept is that computers are authenticated on the wireless network and data transmissions are encrypted, such that a level of wireless security exists that is equivalent to the security in a wired Ethernet network. To increase security on a wireless network, 802.11b networks can also implement a unique 32-bit Service Set Identifier, or SSID, for each wireless client that connects to an access point. The SSID is used to distinguish one wireless LAN (WLAN) from another WLAN. WEP most often has a 64-bit key (10 characters). This is also referred to as 40-bit encryption because only 40 bits are configurable. The other 24 bits are automatically configured. Other versions of WEP include a 128-bit key (26 characters) and a 256-bit key (58 characters). WPA has three different key levels as well. The 64-bit key uses 8 characters. The 160-bit key uses 20 characters. The 504-bit WPA2 key uses 63 characters. WEP is not used on 802.3 Ethernet networks or 802.5 Token-Ring networks. A Bluetooth network, which is wireless, uses a link key for authenticating devices on the network. The link key is a shared 128-bit secret key that is established during a special pairing session.

Which device is also known as a base station?

An access point (AP) is also known as a base station. An AP is used to connect a wireless network to a wired network. An AP translates wireless signals received from a wireless network to signals that are deciphered by a wired network. Each AP that is configured for a wireless network has a specified range. If wireless devices are within the range and have appropriate access to the wired network, these wireless devices will be able to connect to the wired network. Sometimes APs are simply used to grant wireless devices access to the Internet. A hub is not known as a base station. A hub is used to connect multiple devices that are on the same logical network. A switch is not known as a base station. A switch is used to connect multiple devices that are on the same or on different logical networks. A switch provides the same function as a hub but provides enhanced network performance and throughput using full-duplex communication. A repeater is not known as a base station. A repeater is used to extend an Ethernet or a wireless network by providing signal amplification.

You are installing the network cabling for your company. A diagram of the cabling is shown in the following image:

Based on the image displayed, you are installing fiber optic cable. Fiber optic cabling has a center glass core that is surrounded by protective materials. Fiber optic cabling transmits light. It provides a higher transmission speed and better security than the other options listed. However, it is the most expensive to implement. UTP cable consists of four pairs of wires, each pair with a specific number of twists to reduce electromagnetic interference (EMI). The wires are contained within a rubber casing. STP cable looks the same as UTP cable except that STP cable will also have an outer shielding material, usually foil, located between the wires and the outer casing. Coaxial cable consists of a single copper core surrounded by plastic insulation. Outside the plastic insulation is a metal shield, which is surrounded by the rubber casing.

Which Internet connectivity type always uses a coaxial (coax) cable to establish a two-way connection to the Internet?

Cable modem-based Internet connections always use standard coax cabling to establish a direct connection to the Internet. Typically, the cable modem connects to the computer by using either an RJ-45 Ethernet cable or a Universal Serial Bus (USB) cable; however, the cable modem connects to the wall jack and Internet Service Provider (ISP) by using coaxial cable. Because coaxial cabling is capable of transmitting multiple frequencies, the same cable can be used for both cable television and cable modem-based Internet connections. Digital subscriber line (DSL) connections and analog modem-based dial-up Internet connections use a standard RJ-11 telephone jack to establish a connection between the modem and the ISP. DSL connections often use the Point-to-Point over Ethernet (PPPoE) technology. Satellite-based connections are available in two types: a one-way satellite connection, and a two-way satellite connection. The one-way connection uses a dial-up modem to transmit to the Internet through the ISP and a satellite dish to receive information that is relayed through a satellite from the Internet. The two-way connection uses the satellite for both transmitting and receiving information. In one-way satellite Internet connectivity, the computer connects to a device that is known as an Indoor Receive Unit (IRU), which connects through a coax cable to the satellite dish. In two-way satellite Internet connectivity, the Internet service is provide by sending and receiving signals via a remote very-small-aperture terminal (VSAT) and then via satellite to a hub telecommunications port (Teleport). The data is then finally relayed via terrestrial Internet.

Which topologies are used in Ethernet networks? (Choose two.)

In the early years of Ethernet, networks were run using bus topologies. Both 10Base2 and 10Base5 networks use a bus topology. However, 10Base2 uses ThinNet cable, whereas 10Base5 uses ThickNet cable. As the demand for LANs grew, so did the wiring standards, adding the use of the star topology for Ethernet networks. An example of Ethernet star topology is the 10BaseT standard, which uses twisted-pair cabling.

Your organization deploys three wireless networks in close proximity. The configuration of the three wireless networks is as follows: SSID: Students - 802.11b using channel 1 SSID: Faculty - 802.11b using channel 6 SSID: Guest - 802.11g using channel 9 You have been asked to deploy a new wireless network for the Research department. This wireless network should only support 802.11g wireless devices and must use a non-overlapping channel that does not interfere with the other wireless networks. The network should be named Research and should not be advertised. When you open the wireless router's interface, the Basic Wireless Settings screen is configured as follows:

For this scenario, you should configure the Wireless Network Mode option as follows: Change the Wireless Network Mode setting to G-Only. Change the Wireless Network Name (SSID) setting to Research. Change the Wireless Channel setting to 5. Change the Wireless SSID Broadcast setting to Disable. For the Wireless Network Mode, the scenario specifically stated that you ONLY want to support 802.11g wireless devices on the network. Because the scenario also stated that you must use a non-overlapping channel, you must choose from channels 1, 5, 9, or 13 for an 802.11g network. Because channels 1 and 9 are already in use and channel 13 is not an option on the router, you must use channel 5. Note that 80211b wireless networks have four non-overlapping channels: 1, 6, 11, and 14. Finally, the scenario stated that the network name should not be advertised, which means that the Wireless SSID Broadcast option should be set to Disable. The correct answer is as follows For testing purposes, you should understand how to configure a wireless router. This includes setting the network mode, the SSID name, and the channel used. You should also understand how to enable/disable SSID broadcast and how to configure MAC filtering. Linksys has an online emulator that will allow you to view the different configurable screens for the various models. The link to the online emulator is given in the References section. When you access this site, you first select the model number you want to emulate. Then you will need to select the firmware version. The emulator will allow you to view all the configurable screens for a Linksys wireless router. We suggest that you spend time familiarizing yourself with wireless configuration settings using this free tool.

Which transmission mode is used in 802.11 WLANs?

In 802.11 Wireless Local Area Networks (WLANs), the data transmission mode is half-duplex. In half-duplex mode, a single communication channel is used for both transmitting and receiving. Because a single channel is used for both sending and receiving traffic, data can travel only one direction at a time. If you have more than one wireless access point in close proximity, you should ensure that each access point uses a different wireless channel to ensure that connection problems do not occur. Mixed mode is not a data transmission mode. In simplex mode, two separate channels are used for transmitting and receiving the signal. 802.11 WLANs do not support simplex transmission through radio frequencies (RF). In full-duplex mode, you can transmit and receive the signal on the same channel at the same time. 802.11 WLANs do not support full-duplex transmission through RF. The 802.11 specification is used to manage wireless networks. Other specifications require the use of cables to connect directly to the devices on the network. For testing purpose, you need to understand the following four wireless specifications as part of the 802.11 specification: 802.11a - This specification uses the 5 GHz frequency and can transmit at 54 megabits per second (Mbps). 802.11b - This specification uses the 2.4 GHz frequency and can transmit at 11 Mbps. 802.11g - This specification uses the 2.4 GHz frequency and can transmit at 54 Mbps. It is compatible with 802.11b. 802.11n - This specification uses the 2.4 or 5 GHz frequency and can transmit at 600 Mbps. However, 300 to 400 Mbps is usually the maximum in most of today's deployments.

You are creating a crossover cable. You know that each end of the crossover cable must be configured differently. Which pins contain the Blue wire?

In a crossover cable, the Blue wire should be in Pin 4 at both ends of the cable. Basically, a crossover cable is wired for the 568A specification at one end and the 568B specification at the other end. The wiring scheme for a crossover cable is shown below: Pin 1 (End 1) - Orange/White Pin 1 (End 2) - Green/White Pin 2 (End 1) - Orange Pin 2 (End 2) - Green Pin 3 (End 1) - Green/White Pin 3 (End 2) - Orange/White Pin 4 (End 1) - Blue Pin 4 (End 2) - Blue Pin 5 (End 1) - Blue/White Pin 5 (End 2) - Blue/White Pin 6 (End 1) - Green Pin 6 (End 2) - Orange Pin 7 (End 1) - Brown/White Pin 7 (End 2) - Brown/White Pin 8 (End 1) - Brown Pin 8 (End 2) - Brown Communication over a crossover cable only occurs over Pin 1, 2, 3, and 6. A crossover cable is an OSI Physical layer (Layer 1) device. A T1 crossover cable is a special crossover cable that is used to connect a PBX to another PBX. To create a T1 crossover cable, the ends should be configured in the following manner: Pin 1 (End 1) - Orange/White Pin 1 (End 2) - Blue Pin 2 (End 1) - Orange Pin 2 (End 2) - Blue/White Pin 3 (End 1) - Green/White Pin 3 (End 2) - Green/White Pin 4 (End 1) - Blue Pin 4 (End 2) - Orange/White Pin 5 (End 1) - Blue/White Pin 5 (End 2) - Orange Pin 6 (End 1) - Green Pin 6 (End 2) - Green Pin 7 (End 1) - Brown/White Pin 7 (End 2) - Brown/White Pin 8 (End 1) - Brown Pin 8 (End 2) - Brown

Your company's WAN connects networks in New York, Atlanta, Dallas, and Boston. Each city is directly connected to every other city. Which physical topology is used for your WAN?

In a mesh topology, every device has a dedicated connection to every other device using a series of point-to-point connections. In the case of a WAN, a mesh topology connects each individual network to each other network in an intranetwork. This type of topology is very expensive because of its redundant links, but it provides a high level of fault tolerance. Therefore, it is typically seen in a WAN environment where fault tolerance is a major concern. The following table lists the advantages and disadvantages of the different network topologies:

Your company has decided to implement a wireless network. The wireless network users must be able to connect to resources on your internal network, including file, print, and DHCP services. All wireless clients will run the Windows XP Professional operating system. Which options should you implement? (Choose all that apply.)

Infrastructure mode allows wireless computers to connect to a LAN, a WAN, or the Internet. This means that infrastructure mode wireless computers can access all computers on the LAN, WAN, and Internet. Infrastructure mode is much more expensive than ad hoc mode to implement because you must configure wireless access points. While infrastructure mode is harder to set up and configure, its management is much easier than with ad hoc mode. To view the strength of the wireless network, open the properties dialog box for the wireless network interface card (NIC). Ad hoc mode allows wireless computers to be configured much faster than infrastructure mode. Ad hoc mode wireless computers all participate in the same network. This means that the ad hoc wireless computers can access each other, but cannot access network resources on a LAN, WAN, or Internet. Ad hoc mode is much cheaper than infrastructure mode to implement. In addition, it is easy to set up and configure and can provide better performance than infrastructure mode. However, it is difficult to manage an ad hoc mode wireless network. Static IP addresses should not be implemented because the corporate network contains a DHCP server. Static addressing refers to the manual configuration of each computer. APIPA should not be used for the same reason. In addition, APIPA is utilized only if a DHCP server is not found. When implementing a wireless network that includes a wireless access point, you can often enable or disable DHCP. If you enable DHCP, devices on the network will be assigned an IP address. If you disable DHCP, the devices will need to have statically configured IP addresses.

Which protocol is used by Active Directory?

Lightweight Directory Access Protocol (LDAP) is used by Active Directory. It is used by applications to access directories. By default, it uses port 389. Server Message Block (SMB) is the application that was responsible for the NetBIOS naming service. NetBIOS names were managed by the old Microsoft WINS servers. It uses port 445. Secure File Transfer Protocol (SFTP) is a secure version of File Transfer Protocol (FTP) that uses an SSH tunnel. While FTP uses port 20 and 21, SFTP uses port 22. Secure Shell (SSH) is a secure remote terminal application that works over the Internet. SSH uses port 22.

Which network topology supports the longest maximum cable length?

Of the choices given, 10BaseF networks, which operate at 10 megabits per second (Mbps), support the longest cable length with a maximum distance of 2,000 meters (m) or 2 kilometers (km). 10BaseF is also known as 10BaseFL; another fiber-optic standard known as 10BaseFP exists, but it never received widespread acceptance. The 100BaseFX standard is identical to 10BaseFL, except that the network speed is 100 Mbps rather than 10 Mbps. Networks configured with a 10Base2 topology support a maximum cable length of 185 m. Networks built on a 10Base5 topology support a maximum cable length of 500 m. The 10BaseT and 100BaseT topologies support a maximum distance of 100 m between two devices.

You administer your company's 100BaseTX Ethernet network. TCP/IP is the networking protocol used on the network. You want the routers on the network to send you notices when they have exceeded specified performance thresholds. Which protocol should you use to enable the routers to send the notices?

Of the protocols presented, you should use Simple Network Management Protocol (SNMP) to enable the routers to notify you when they exceed specified performance thresholds. SNMP is a protocol in the Transmission Control Protocol/Internet Protocol (TCP/IP) protocol suite that enables the collection of data about various devices connected to a TCP/IP network, including bridges, hubs, and routers. Each SNMP-compatible device has a Management Information Base (MIB) database that defines the type of information that can be collected about the device. You can also configure SNMP traps to analyze network performance and network problems. A trap is a message that an SNMP-compatible device sends when the device has exceeded a performance threshold. You can configure SNMP to send traps to the network management software you are using, to your e-mail address, or to another destination. Address Resolution Protocol (ARP) is used on a TCP/IP network to resolve Internet Protocol (IP) addresses to media access control (MAC) addresses. TCP/IP uses IP addresses to identify hosts, whereas Ethernet uses MAC addresses to identify network nodes. For Ethernet and TCP/IP to interoperate, a host's IP address must be resolved to a MAC address. You cannot use ARP to notify you when network devices have exceeded performance thresholds. Simple Mail Transfer Protocol (SMTP) is used to transfer e-mail messages from e-mail clients to e-mail servers. SMTP is also used to transfer e-mail messages between e-mail servers. SMTP will not send traps when network devices have exceeded performance thresholds. Telnet is a terminal emulation protocol. You can use Telnet to establish a remote session with a server from a local host through a terminal window to issue commands on the remote server. Telnet client software provides you with a text-based interface and a command line from which you can issue commands on a server that supports the Telnet protocol. Telnet will not send notices when network devices have exceeded established performance thresholds.

Which technology has the SHORTEST maximum range?

Of the technologies listed, Bluetooth 2.0 has the shortest maximum range. The following list includes the maximum range of the major wireless technologies included on the A+ exam: Bluetooth 1.0 - 100 meters or 300 feet Bluetooth 2.0 - 10 meters or 33 feet Bluetooth 3.0 - 1 meter or 3 feet 802.11a - indoors, 150 feet; outdoors, 390 feet 802.11b - indoors, 150 feet; outdoors, 460 feet 802.11g - indoors, 125 feet; outdoors, 460 feet 8021.11n - indoors, 230 feet; outdoors, 820 feet

Which technology has the LONGEST amount of latency?

Of the technologies listed, satellite has the most (or longest) latency. Latency is defined as the amount of delay a network can experience. Latency can be affected by distance, the number of routers between two hosts, and the amount of traffic on the network. None of the other technologies have latencies as high as satellite. Of the technologies listed, an F1 line has the lowest latency.

While performing routine maintenance on your company's firewall, you discover that port 3389 is open. Which service uses this port?

Port 3389 is used by the Remote Desktop Protocol (RDP). RDP is the protocol used by Remote Assistance and Remote Desktop in Windows. If this port is closed on your firewall, you will not be able to give remote assistance to remote users. File Transfer Protocol (FTP) uses port 20 and 21. FTP is a tool that allows a user to transfer files over a network. These ports should only be left open if you specifically use FTP. HyperText Transfer Protocol (HTTP) uses port 80. HTTP is the protocol used by Web pages. Secure HyperText Transfer Protocol (HTTPS) uses port 443. HTTPS is the protocol used by secure Web pages. Post Office Protocol (POP) version 3 uses port 110. POP3 is a mail protocol that retrieves e-mail from an e-mail server. On most networks, this port is open. Telnet uses port 23. Telnet is a tool that allows a user to connect to other computers. Simple Mail Transfer Protocol (SMTP) uses port 25. SMTP is a mail protocol commonly used for outgoing e-mail. On most networks, this port is open. Network News Transfer Protocol (NNTP) uses port 119. NNTP is a news protocol. Internet Message Access Protocol (IMAP) uses port 143. IMAP is a mail protocol.

Which statement is incorrect for routers?

Routing does not occur at OSI Layer 4, the Transport layer. The Transport layer provides transfer of data between end systems or hosts. This layer is accountable for end-to-end error recovery and flow control. Routing occurs at the Network layer, also referred to as OSI Layer 3. The Network layer provides switching and routing technologies for transmitting data packets from one node to another. All other options are true for routers. Routers are used to forward data packets across networks. Routers can be installed on a network's gateway to establish a connection between two LANs or WANs or a LAN and its ISP. Routers can use the ICMP protocol to communicate with other routers. The ICMP protocol assists a router in providing a default gateway setting to a host. Routers can also send ICMP messages to forward a host to another router.

What is the main difference in the physical composition of UTP and STP cable?

Shielded twisted-pair (STP) cables are identical to UTP except for the shielding that encloses the twisted pairs. This metallic shield protects the STP cable from interference caused by fluorescent light fixtures, motors, and other electromagnetic interference (EMI) sources. STP cables can be used in any implementation where UTP cables are used, but they are generally only used when shielding from EMI is required because it is more expensive than using UTP cables. UTP cables are used in telephone and network wiring. These are the cables most commonly used in networks today.

What is the transmission distance supported by single-mode fiber optic cable?

Single-mode fiber supports a transmission distance of approximately 20 miles, or more. Single-mode fiber has an advantage over the multi-mode fiber and all other transmission mediums in terms of transmission distance. Single-mode fiber does not support a transmission distance of 50 feet, 3000 feet, or 74 miles. The coaxial cable that is used in a 10Base2 network is known as RG-58 or ThinNet. The coaxial cable that is used in a 10Base5 network is known as RG-8 or ThickNet. A ThinNet cable supports a transmission range up to 185 meters, and a ThickNet cable can support transmission up to 500 meters. RG-8 ThickNet cabling is best to use if the data rate speed is not an issue and the segment length must be 500 meters long. Multi-mode fiber optic cable supports a transmission distance of 3000 feet. Unshielded twisted pair (UTP) or shielded twisted pair (STP) cables have a transmission range up to 100 meters or 328 feet.

Your organization uses an 802.5 network with an MAU. What is the physical topology of this network?

The IEEE 802.5 standard, known as Token Ring, functions as a logical ring but uses a physical star topology. Like an Ethernet star topology, a Token Ring network uses a central device to connect all the network devices. This device is known as a multistation access unit (MAU). Typically, either UTP or STP twisted-pair cabling, using RJ-45 connectors, links computers to the MAU.

Which characteristic is common to 10Base2, 10BaseT, and 100BaseTX?

The "Base" in each standard's name indicates that it uses the baseband signaling method for communication over the network. This means that only one signal at a time is sent onto the network medium. This is the direct opposite of broadband, which multiplexes the signals to allow multiple signals on the medium. The naming standard is the same for the different Ethernet types. The first number of each standard indicates the transmission speed in Mbps. The middle portion indicates the signaling type, and the last portion indicates the transmission medium. For example, the "100" in 100BaseTX indicates that it can transmit at a speed of 100 Mbps; "Base" indicates that it uses the baseband transmission method, and "TX" indicates twisted-pair cable for the network medium. The cable type is not very intuitive and can be difficult to decipher. 10Base2, 10BaseT, and 100BaseTX do not transmit at the same rate. 10Base2 and 10BaseT transmit at 10 Mbps, whereas 100BaseTX transmits at 100 Mbps. They do not use the same transmission medium: 10Base2 uses coaxial cable, whereas 10BaseT and 100BaseTX use twisted-pair. Their physical topologies are also different: 10Base2 uses a bus topology, whereas 10BaseT and 100BaseTX use a physical star topology. However, they do share the same logical topology (bus). 1000BaseT networks, also called Gigabit Ethernet, transmit data faster than the other Ethernet standards at 1 Gbps or 1000 Mbps.

Which IP address is used by a Class A private network?

The 10.0.0.0 address is a Class A IP address for private networks. Private network IP addresses cannot be used on the Internet. The 172.16.0.0 address is a Class B IP address for private networks. The 192.168.0.0 address is a Class C IP address for private networks. The 127.0.0.1 address is not reserved for private networks. This IP address is the software loopback address.

Which IP address is used by Class B private networks?

The 172.16.0.0 address is used by Class B private networks. Private network IP addresses are those addresses which are reserved for use on private networks, and cannot be used on the Internet. The valid IP address ranges for private networks are 10.0.0.0 to 10.255.255.255, 172.16.0.0 to 172.31.255.255, and 192.168.0.0 to 192.168.255.255. If you plan to deploy a private IP address range on your network and need to provide Internet access as well, a Network Address Translation (NAT) server will be needed. The 10.0.0.0 address is a Class A IP address for private networks. The 192.168.0.0 address is a Class C IP address for private networks. The 127.0.0.1 address is the software loopback address. The following are the five valid IP v4 address classes: Class A - 1.0.0.0 to 126.0.0.0 Class B - 128.0.0.0 to 191.255.0.0 Class C - 192.0.1.0 to 223.255.255.0 Class D - 224.0.0.0 to 239.255.255.255 Class E - 240.0.0.0 to 255.255.255.255 Classes A, B, and C are valid addresses used on IP networks. Class D addresses are reserved for multicasting. Class E addresses are considered experimental or research addresses and should never be used.

Which radio frequency band does the 802.11b standard use?

The 802.11b standard is a wireless standard that operates in the 2.4 GHz radio frequency band. This frequency range (2.400 - 2.483 GHz) of the radio spectrum was intentionally set aside for wireless networking by the Federal Communications Commission (FCC) in 1985. It is known as the Instrumentation, Scientific, and Medical (ISM) frequency band. The ISM band offers as many as 14 channels. However, in the United States, there are 11 channels available for use. Operating in this band means that the user does not need to obtain a radio operator's license. If two wireless access points are located near each other, you should configure each wireless access point to use a different channel to prevent interference between the two wireless access points.

Which component in a network is used as an access point to another network?

The default gateway, or router, component is used as an access point to another network. In a network, a default gateway has its own address, known as a gateway address, which can be specified on a user's computer to enable these computers to access outside networks. In a wired network, routers can be used as default gateways, and in a wireless network, you can configure wireless access points as routers to make them act as default gateways. The proxy server component allows client computers on a network to indirectly connect other network services. You can configure various types of proxy server depending upon the business requirements: Caching Web, Secure Sockets Layer (SSL), intercepting, open, reverse, or split proxy. A proxy server makes a single connection available to many network users. Proxy servers filter requests and increase performance. A proxy server can be configured to allow only specific types of connections based on protocol type or even user name. The firewall component is a hardware or software that is used to provide security to a network against threats and attacks. A firewall secures a network from unauthorized users. The DMZ component, also referred as perimeter network, is located between an internal and external firewall where the internal firewall is connected to the internal network, and the external firewall to the outside network. A DMZ is typically implemented in a network where servers are configured to be accessed from outside networks.

Match the connectors on the left to the cable types on the right. Move the correct items from the left column to the column on the right to match the connector with the correct cable type.

The following is the correct matching for connectors and cable types: BNC - coaxial cable SC - fiber-optic cable RJ-45 - twisted-pair cable Coaxial cable can also use an F-connector. Fiber-optic cable can also use an ST or LC connector. Twisted-pair cable can also use an RJ-11 connector. For twisted pair cable, an RJ-11 connector is used in telephone deployments and an RJ-45 connector is used in network deployments.

Match the cable types on the left with the appropriate maximum distance and speed option on the right. Move the correct items from the left column to the column on the right to match cable type with the correct maximum distance and speed.

The following is the correct matching of the cable types with maximum distance and speed options: Cat5 - Up to 100 m and 100 Mbps Cat6 - Up to 100 m and 10 Gbps Multi-mode Fiber - Up to 500 m and 10 Gbps Single-mode Fiber - Up to 40 km and 10 Gbps ThickNet - Up to 500 m and 10 Mbps ThinNet - Up to 185 m and 10 Mbps

Which applications use UDP?

User Datagram Protocol (UDP) provides two services that Internet Protocol (IP) does not: a port number to help distinguish different user requests and, optionally, a checksum capability to verify that the data arrived intact. UDP works at the Transport layer of the OSI model. Network applications that want to save processing time use UDP because they have very small data units to exchange, and therefore require a small amount of reassembly. The Trivial File Transfer Protocol (TFTP), Network File System (NFS), and Simple Network Management Protocol (SNMP) use UDP instead of Transmission Control Protocol (TCP). TFTP is a network application that is simpler than File Transfer Protocol (FTP), but less capable. It is used when user authentication and directory visibility are not required. TFTP, FTP, NFS, and SNMP all work at the Application layer of the OSI model. Simple Mail Transport Protocol (SMTP) is usually implemented to operate over TCP port 25. SMTP is the default protocol for sending e-mail in Microsoft operating systems. SMTP works at the Application layer of the OSI model. FTP is used to transfer files between an FTP server and a client using IP.

What is the network prefix that is used to denote an unsubnetted Class C IP address?

The network prefix /24 is used to denote an unsubnetted Class C IP address. Class-based IP addresses were the first types of addresses assigned on the Internet. The first octet of a Class A IP address is from 1 through 126 in decimal notation; the first octet of a Class A IP address is the network address. The first octet of a Class B IP address is from 128 through 191 in decimal notation; the first two octets of a Class B IP address are the network address. The first octet of a Class C IP address is from 191 through 223; the first three octets of a Class C IP address are the network address. Each class has a default subnet mask. The default subnet mask for a Class A subnet is 255.0.0.0. The default subnet mask for a Class B network is 255.255.0.0. The default subnet mask for a Class C network is 255.255.255.0. Subnetting was introduced to enable more efficient use of the IP address space. In subnetting, some host bits of a Class-based IP address are used as network address bits to enable smaller groupings of IP addresses to be created than the groupings offered by class-based IP addresses. For example, you have an office with 200 computers that reside on four separate networks that consists of 50 computers each. If each network has been assigned its own Class C IP address range, then 204 IP addresses will not be used in each range, for a total of 816 wasted IP addresses. With subnetting, a single Class C IP address range can provide IP addresses for the hosts on all four networks. If you subnetted a single Class C IP address range, then only 48 IP addresses would be wasted. A subnet mask is a 32-bit binary number that can be compared to an IP address to determine which part of the IP address is the host address and which part of the IP address is the network address. Every 1 bit in a subnet mask indicates a bit in the network address, and every 0 bit in the subnet mask indicates a bit in the host address. For example, on a network that uses an unsubnetted Class C IP address range, the IP address 192.168.0.1 has a subnet mask of 255.255.255.0. In binary notation, 255 is represented as 11111111. In binary notation, the subnet mask 255.255.255.0 is represented as 11111111 11111111 11111111 00000000. The binary representation of the IP address 192.168.0.1 is 11000000 10101000 00000000 00000001. The following is a comparison of the binary subnet mask and the binary IP address: 11111111 11111111 11111111 00000000 Subnet Mask 11000000 10101000 00000000 00000001 IP Address From this comparison, you can see that the first 24 bits of the IP address, or 192.168.0 in decimal notation, are the network address, and the last eight bits of the IP address, or 1 in decimal notation, are the host address. Another method, called a network prefix, is also used to determine which part of an IP address is the network address and which part of an IP address is the host address. The network prefix method appends a slash (/) character and a number after the IP address, as in the following example: 192.168.0.1/24 In this example, the network prefix indicates that the first 24 bits of the IP address, or 192.168.0 in decimal notation, are the network address and the last 8 bits of the IP address are the host address.

Match the protocol from the left with the default port it uses on the right. Move the correct items from the left column to the column on the right to match the protocol with the correct default port.

The protocols given use these default ports: Port 21 - FTP Port 110 - POP3 Port 143 - IMAP Port 443 - HTTPS Port 3389 - RDP FTP also uses port 20, but it was not listed in this scenario.

To protect wireless access points, which guidelines should you follow? (Choose all that apply.)

To secure your wireless network, you must change the default administrator name and password on the wireless access points. By default, wireless access points are supplied by manufacturers with a default administrator name and password. To prevent unauthorized users from accessing your wireless network, you must change the default administrator name and password. To protect wireless access points, you should also change the default Service Set ID (SSID) on wireless access points. All wireless access points have a default SSID; you must change the SSID of your wireless access points to something unique. Changing the SSID prevents your wireless network from overlapping with other networks using the same default SSIDs, and from unauthorized users. You should also disable the SSID broadcasts on the network. Finally, you should not enable Wired Equivalent Privacy (WEP). WEP is a commonly used wireless encryption method. However, WEP is easily compromised. Networks should use Wi-Fi Protected Access (WPA) version 1 or 2 to provide better security. To prevent unauthorized users from accessing your wireless network when you are not using the network, you must power-off the wireless access points. You could also configure MAC address filtering on the wireless access points to prevent unauthorized computers from connecting. To configure a wireless network, you should configure the following: SSID, encryption type , encryption key, and channel.

Which technology allows voice data to be transmitted over a company's computer network?

Voice over Internet Protocol (VoIP) allows voice data to be transmitted over a company's computer network. It uses less bandwidth than a traditional telephone call. The benefits provided by VoIP include flexibility, reduced operating costs, scalability, infrastructure simplification, and improved productivity. A good example of the need for VoIP is when a company needs to be able to transmit both voice and data communication, but wants to cut costs in both areas. VoIP phones are specially designed to work over a VoIP network. A demilitarized zone (DMZ) is a portion of a network that is protected by firewalls. It provides corporate services to the Internet. These services can include an Internet server, FTP server, and e-mail server. A good example of the need for a DMZ is when a customer needs to access his sales records on your server. A virtual private network (VPN) is a network that is implemented on a corporate network to allow remote computers to connect securely to the internal network. A good example of the need for a VPN is when a remote salesperson must transfer contract data to the corporate office. An intranet is a corporate network that can only be accessed locally by authorized users. A good example of the need for an intranet is when employees need to access their employment records.

You want to set up a small office wireless network for your company. To provide the best security, you plan to implement Wi-Fi Protected Access (WPA) to provide maximum security. When you configure the first Windows XP Professional SP 1 laptop, WPA is unavailable. What should you do?

WPA is not supported by Windows XP Professional. To be able to use WPA, you must install Service Pack 2. You may need to reboot the computer after configuring WEP. You will need to know the WEP key to connect to a WEP-protected wireless network. You may need to log in with an administrator account to be able to configure WEP. But if WEP is missing altogether, it is a sign that Service Pack 2 is not installed. WEP is not as secure as WPA.

Which WPA version requires the use of a RADIUS authentication server?

WPA-Enterprise requires the use of a RADIUS authentication server. WPA-Enterprise is intended for large networks. It is also referred to a WPA-802.1x. None of the other options is correct. WPA2 is more secure than WPA. WPA-Pre-shared Key (WPA-PSK), also known as WPA-Personal, is for use in small home or office networks.

You need to connect two computers for a customer. The customer does not have a network and does not wish to purchase a concentrator, but both computers include functional Ethernet network interface cards with RJ-45 connectors. Which component will allow you to meet your customer's needs?

You can use a crossover cable to connect two computers directly through the RJ-45 connectors on their Ethernet network cards. A crossover cable consists of a standard 10BaseT cable with RJ-45 connectors that have specific pin contacts reversed. RJ-45 connectors, when used to connect Ethernet interface cards, support a 10BaseT network topology. On a standard 10BaseT network, computers' network interface cards must connect to a concentrator, often referred to as a hub, before they are able to communicate with other computers. The reversed pin contacts in crossover cables accomplish the same signal conditioning that Ethernet concentrators are responsible for on a typical 10BaseT network. One reason to use a crossover cable is to connect two computers directly without incurring the cost of a concentrator. Null-modem cables, which are serial cables with some pin contacts reversed, also allow direct communication between two computers. Use of the term null-modem became common because communications through these modified serial cables use modem commands and protocols, but actual modems do not have to be physically present. Standard serial ports are adequate for initiating and maintaining a connection. An AGP card is a graphics card designed to connect to a computer's AGP slot. Passive hubs are concentrators that require no external electric power. The 10BaseT standard does not include specifications for passive hubs; consequently, 10BaseT concentrators are all active, which means they require a source of electric power. A protocol analyzer is a tool that allows the capture and display of packets traveling across a network.

Which tools can you use to measure the length of a cable based on the time required for an energy pulse to travel down the cable and return to the tool?

You can use a time-domain reflectometer (TDR) to measure the length of the cable based on the time required for an energy pulse to travel down the cable and return to the TDR. If the cable length indicated by a TDR is less than expected, then you can determine that a cable problem exists at the position indicated by the TDR. For example, you use a TDR on a cable that you expect to be 100 meters (m) in length. The TDR indicates, however, that the cable is 80 m in length. You can thus determine that a problem, such as a break in the cable, exists 80 meters down the cable from your present location. You can use a crimper to attach a connector to each end of a cable and create a patch cable. For example, you can use an RJ-45 crimper to attach RJ-45 connectors to the ends of Category 5 unshielded twisted-pair (CAT5 UTP) cable to create a patch cable for a 100BaseTX Ethernet network. A punchdown tool is similar to a crimper, but a punchdown tool is used for attaching cable to a punchdown block or patch panels. A crossover cable is a network cable that directly connects the sending pins on one network interface card (NIC) or hub with the receiving pins on another NIC or hub. You can use a crossover cable to connect two hubs or to connect two computers from one NIC to the other NIC. A hardware loopback directly connects the sending and receiving pins on the same NIC. You can use a hardware loopback and a NIC's diagnostic utility to determine whether a NIC is correctly sending and receiving data. There are also loopback plugs that can test the functionality of serial and parallel ports. Another tool that you must be familiar with is a toner probe, which is an electronic test instrument to help trace wires. One part (the tone generator) induces a tone on a pair of wires. The other you part (the tone probe) detects the tone at the other end to trace where the wires go. You can trace wires through walls using a toner probe and determine which pair is carrying the signal you induced at the other end. A cable tester is used verify the electrical connections in a cable or other wired assembly. Generally a cable tester consists of an electric current source, a volt meter, and a switching matrix used the current source and volt meter to all of the cable's contact points.

You configure a Bluetooth network that connects a user's laptop computer with his cell phone. Which type of network have you created?

You have created a personal area network (PAN). A PAN can contain a computer, cell phone, personal digital assistant (PDA), or other personal device, and operates using Bluetooth, infrared, USB, or FireWire connectivity. A local area network (LAN) is a group of computers and other devices that are connected using a network. A LAN usually has an uplink to the Internet. A wide area network (WAN) is similar to a LAN, but usually covers a broader geographic area than a LAN. A virtual private network (VPN) is a network that uses a public network, such as the Internet, to provide remote users access to private resources. Another type of network that you must understand for the A+ exams is a metropolitan area network (MAN). This network spans a city or large campus.

Which information must be provided to a wireless device to enable it to connect to a wireless network?

You must provide the service-set identifier (SSID) to a wireless device to enable it to connect to a wireless network. The SSID in a wireless network is the name of the network to which a wireless device connects. Only one SSID can be associated with an access point. When a wireless device sends data packets over a wireless network, each data packet contains a 32-character identifier that is used to identify the wireless network. The 32-character identifier is the SSID of the wireless network. Wireless networks are differentiated by SSID. By default, the SSID is broadcast. To provide better security, you should configure the wireless access point to NOT broadcast the SSID. The AP information does not need to be provided to a wireless device to enable the device to connect to a wireless network. An AP acts as a hub between the wireless devices and the local area network (LAN), which is typically a wired network. In most cases, a wireless device automatically detects an AP and connects to the AP and subsequently, to the wired network. The Wired Equivalent Privacy (WEP) information does not need to be provided to a wireless device for connecting to a wireless network. WEP is a protocol used for encrypting the data packets being transmitted over the wireless network. WEP would need to be configured if a connection is being made to a secured WEP wireless network. If the wrong WEP key is entered, the network connection will fail. The WPA information does not need to be provided to a wireless device to enable the device to connect to a wireless network. The WPA protocol offers enhanced data encryption and user authentication. A number of weaknesses in WEP, such as user authentication, were addressed by WPA. WPA would need to be configured if a connection is being made to a secured WPA wireless network.

You have two computers running Windows Vista at your home. You plan to use a crossover cable to connect both computers. Which hardware device should you use with the crossover cable to establish network connectivity between the computers?

You require a network interface card (NIC) in each computer to use a crossover cable to establish network connectivity between the two computers. A crossover cable does not require any other special equipment to connect the two computers. A bridge is a hardware device that connects two portions of a network or two similar networks. This device is used to reduce network traffic by keeping network traffic separate at each segment. You can use a hub or switch to connect multiple computers in a network. Switches are more efficient than hubs because switches forwards packets only to the intended recipient(s), while hubs forward packets to all the nodes.

You need to allow users to connect to your network remotely from the Internet. The connection must be secure. What should you configure?

You should configure a VPN to allow users to connect to your network remotely from the Internet in a secure manner. A firewall is used to screen your network from unwanted traffic. A screened subnet, or DMZ, is a subnet on your local network that contains computers that are commonly accessed from the Internet. The computers on the DMZ are usually screened from the local network using a firewall. This ensures that Web users only access public computer and cannot access computers on the private network. A small office home office (SOHO) network is one that includes all the devices in a single office or home. A local area network (LAN) is one that includes all the devices of a company or in a building. A wide area network (WAN) is one that covers a much wider geographic area than a LAN. A metropolitan area network (MAN) is one that covers a city or metropolitan area.

You are an IT technician at your company. The company has two small offices in different cities. The company's head office contains a DNS server and a DHCP server. The branch office does not contain a DHCP server. A user travels frequently between the head office and the branch office. You are configuring the IP address on this user's laptop. You are required to ensure that the user is able to connect to the Internet from both offices. How should you configure the Internet Protocol (TCP/IP) Properties dialog box on the user's laptop while expending the least administrative effort?

You should configure the General tab to use the DHCP server at the head office and configure a static IP address from the branch office network range on the Alternate Configuration tab. Dynamic Host Configuration Protocol (DHCP) is used to assign IP addresses automatically to the hosts on the network. DHCP provides unique IP address to all the hosts. You should configure DHCP to assign IP addresses automatically. In this scenario, the head office contains a DHCP server. Therefore, configuring the General tab to use the DHCP server will ensure that the user's laptop automatically receives the IP address settings from the DHCP server when the user is in the head office. When the General tab is configured to use a DHCP server and there is no DHCP server located on the network, the alternate IP address settings are checked by the computer. If the alternate IP address settings are also not configured, then an IP address from the Automatic Private IP Addressing (APIPA) range (169.254.0.0 -169.254.255.255) is assigned to the computer. To ensure that the user is able to connect to the Internet from the branch office, you should configure the Alternate Configuration tab on the user's laptop to use a static IP address from the IP address range of the branch office network. This will ensure that the user's laptop uses the branch office's IP address settings when the user is in the branch office. You should not configure the General tab and the Alternate Configuration tab to use the DHCP server. There is no DHCP server on the branch office network in this scenario. Therefore, the user's laptop will receive an IP address from the APIPA range while in the branch office. This will not allow the user to connect to the Internet while in the branch office. You should not configure a static IP address from the head office network range on the General tab, and configure a static IP address from the branch office network range on the Alternate Configuration tab. The head office contains a DHCP server in this scenario. Therefore, you should configure the General tab to use the DHCP server. You should not configure the General tab and the Alternate Configuration tab to use a static IP address from the branch office network range. Configuring the General tab to use a static IP address from the IP address range of the branch office network will not allow the user to connect to the Internet from the head office. To configure the IP address on a Windows XP computer, you should go into Control Panel. Double-click Network Connections. Right-click Local Area Connection, and click Properties. To configure the IP address on a Windows Vista or Windows 7 computer, you should go into Control Panel. Click Network and Internet, and then click Network and Sharing Center. Click Manage Network Connections. Right-click the connection you want to configure, and click Properties

Your company has a wired 1000BaseT small office network that connects to the Internet via a DSL connection. Users have been issued laptop computers that have wireless network cards. A wireless network must be set up for these users. The wireless network will need access to the internal network and to the Internet. While configuring the wireless access point, you change the administrative user name and password and change the SSID from its default setting. Then you disable SSID broadcasts. Finally, you enable MAC filtering and configure the list of MAC addresses that are allowed to connect via the wireless network. Now you need to connect the wireless access point to your local network. To which device should it be connected?

You should connect the wireless access point to a router. This will ensure that the wireless clients can connect to the internal network and to the Internet. You should not connect the wireless access point to the DSL modem. No part of your internal network should be directly connected to an Internet access point. You should install a firewall between the DSL modem and your internal network to provide security. You should not connect the wireless access point to the firewall. Wireless access points should be connected to routers. A firewall should be installed between the internal network and the Internet access point (DSL modem). This will ensure that unauthorized access to the internal network is prevented. You should not connect a wireless access point to a hub. Hubs are connected to routers. Routers are connection devices that manage separate subnets in a network. Another network device that you need to understand is a gateway. A gateway interconnects two networks with different network protocols. You can use MAC filtering on a wireless network to ensure that only certain clients are able to connect to the wireless network. MAC filtering is most effect in a small office where a defined number of specific wireless devices are used.

You have implemented a hardware firewall on a small office network. You need to ensure that all HTTP packets are automatically sent to the Web server. What should you do?

You should enable port forwarding. Port forwarding allows you to enable a specific port in the firewall and direct traffic that comes from outside your network to a specific IP address. For example, in this scenario, you would open port 80 on the firewall and configure port forwarding to forward all incoming traffic to the Web server. You should not enable port triggering. Port triggering allows you to open an incoming connection to one computer based on an outgoing connection. You should not enable Network Address Translation (NAT). NAT causes your entire network to appear as a single entity on the Internet. You should not enable Quality of Service (QoS). QoS allows you to limit the bandwidth available for data based on the protocol used, the IP address, or other parameters. It is usually configured on routers. Another router feature that you must understand for the A+ exams is Wi-Fi Protected Setup (WPS). This feature was intended to make secure wireless connections easier to configure. WPS is usually configured using a button on the router or using a password or code. However, WPS is not secure enough because hackers can guess this code with a little effort.

Your company has a wireless network for its small office network. The wireless network does not broadcast its Service Set ID (SSID). You configure a user's Windows Vista computer to connect to the wireless network by manually setting the SSID. You need to ensure that the user's computer does not send probe requests to discover if the wireless network is in range.

You should ensure the Connect even if the network is not broadcasting option on the Connections tab of the wireless connection is cleared. If this option is enabled, probe requests are sent to discover if a non-broadcast network is in range. You should not change the configuration of the Connect automatically when this network is in range option. This option ensures that the connection is re-established when the wireless network is detected. When you disable automatic configuration of an SSID, the SSID is not automatically transmitted to all computers within the wireless network range. This provides a low level of security. The only way to connect to the wireless network is to enter the SSID manually.

You are creating a wireless network for your company. You need to implement a wireless protocol that provides maximum security while providing support for older wireless clients.

You should implement WPA. WPA was created to fix core problems with WEP. WPA is designed to work with older wireless clients while implementing the 802.11i standard. WPA uses Temporal Key Integrity Protocol (TKIP) to ensure that a new encryption key is provided for every packet that is sent. WAP is the default protocol used by most wireless networks and devices. However, because WAP can access Web pages and scripts, the opportunity for malicious code to damage a system is great. WAP does not provide maximum security. It is considered the weakest wireless protocol. WEP is the security standard for wireless networks and devices that uses encryption to protect data. However, WEP does have weaknesses and is not as secure as WPA or WPA2. WPA2 completely implements the 802.11i standard. Therefore, it does not support the use of older wireless cards. Identification and WPA2 are considered the best combination for securing a wireless network. WPA2 is much stronger than WPA. In addition, you can implement WPA2 with TKIP or Advanced Encryption Standard (AES) to provide greater security. WPA2-AES is stronger than WPA2-TKIP. WPA2 uses AES secure the wireless environment.

A salesman for your company travels primarily in Europe and Asia. You need to provide him with a wireless Internet technology that will work internationally on his laptop and that can be installed easily when he arrives at a new location. Which technology should you install?

You should install Global System for Mobile Communications (GSM) cellular on the salesman's laptop. This cellular technology is used globally. A cellular WAN card can provide an Internet connection in most locations for a laptop computer. You should not install Code Division Multiple Access (CDMA) cellular on the salesman's laptop. This technology is primarily used in the United States. This technology provides faster connection speeds than GSM cellular. You should not install satellite on the salesman's laptop. A satellite computer connection will require more configuration when the salesman arrives at a new connection. Most satellite connections that are used with computers include a satellite and a satellite modem. To install this equipment, the satellite would need to be repositioned and the satellite modem would need to be reconfigured with the appropriate data. You should not install Bluetooth on the salesman's laptop. Bluetooth is a short-range wireless technology used to interconnect many devices, such as cell phone headsets, keyboards, and so on.

You want to allow Wireless Zero Configuration to manage wireless networks on your Windows XP Professional computer. What should you do?

You should select the Use Windows to configure my wireless network settings option on the Wireless Networks tab of the Wireless Network Connection Properties dialog box. Enabling this option allows the Wireless Zero Configuration service to manage your network connections. This service ensures that a Windows XP Professional computer automatically connects to and configures any preferred networks that it detects. If the Wireless Zero Configuration service does not automatically start when a computer boots, then the wireless networks that are managed by the Wireless Zero Configuration service will not be detected and connected. You should not clear the Use Windows to configure my wireless network settings option on the Wireless Networks tab of the Wireless Network Connection Properties dialog box. This would prevent the usage of Wireless Zero Configuration. You should not select or clear the Automatically connect to non-preferred networks option in the Advanced dialog box. To open the Advanced dialog box, you should click the Advanced button on the Wireless Networks tab of the Wireless Network Connection Properties dialog box. The Advanced dialog box has three options in the Networks to access section as shown below: Any available network (access point preferred) - This option allows you to connect to both ad hoc and infrastructure mode wireless networks, but provides preferential treatment to access point (infrastructure mode) wireless networks. Access point (infrastructure) networks only - This option prevents your computer from joining an ad hoc wireless network. Computer-to-computer (ad hoc) networks only - This option prevents your computer from joining an infrastructure mode wireless network. The final option on the Advanced dialog box is the Automatically connect to non-preferred networks option. By default, this option is disabled, which means that your Windows XP Professional computer will NOT automatically connect to non-preferred networks. If you enable this option, Windows XP Professional will automatically connect to both non-preferred and preferred networks.

You are setting up an 802.11a wireless network in a small office environment that includes three wireless access points. The wireless access points are at least 15 meters apart and are configured for automatic channel setting. Each time you turn the wireless access points on, the wireless access points choose the same channel. You need to ensure that the access points choose separate channels to prevent interference, using the least amount of administrative effort. What should you do?

You should start each wireless access point at a separate time. This will allow each access point to select a channel. Then, when the next access point is booted, it will detect the other access points' channels and use another channel besides the ones detected. 802.11a wireless access points have eight available non-overlapping channels: 36, 40, 44, 48, 52, 56, 60, and 64. 802.11a products need to be configured for automatic channel selection. Therefore, you cannot manually configure the channel. With the automatic channel selection feature, 802.11a wireless access points can detect other access points and configure their channel accordingly. This is the reason that it is important to start 802.11a wireless access points at a separate time. The suggested range for 802.11a wireless access points is 30 meters in an open space, and 10 meters in an office environment. You should not increase the distance between the wireless access points to at least 20 meters. For 802.11a wireless access points, the suggested distance in an office environment is 10 meters. You should not manually configure each of the access points to use channels 1, 6, and 11, respectively. These are the non-overlapping channels used by 802.11b and 802.11g devices. You should alternate between these three channels when using 802.11b or 802.11g wireless access points. The suggested range for 802.11b and 802.11g wireless access points is 120 meters in an open space and 30 meters in an office environment. You should not reduce the signal strength on each access point. This would require more administrative effort than is necessary to fix your problem. In addition, reducing the signal strength could cause problems for some wireless clients that are now outside the new range. It is much simpler to turn the wireless access points on at different times.

You administer a TCP/IP network. You want to enable the hosts on your network to be automatically configured with IP configurations, such as IP address, subnet mask, and default gateway address. The IP configurations should be leased to the clients for a limited period. Which protocol should you use to accomplish this task?

You should use Dynamic Host Configuration Protocol (DHCP) to automatically configure the hosts on your network with IP configurations. DHCP was designed to automatically configure frequently moved, fully boot-capable computers, such as laptop computers, with IP configurations. You can use DHCP to configure such IP settings as IP address, subnet mask and default gateway address. Typically, DHCP information is leased to a client for a limited period. DHCP clients usually release DHCP information when they are shut down. When a DHCP client retrieves IP configurations from a DHCP server, the DHCP client is not necessarily configured with the same IP configurations that it was configured with on previous occasions. BOOTstrap Protocol (BOOTP) is a host configuration protocol that was designed before DHCP. BOOTP was designed to configure diskless workstations with IP configurations. BOOTP does not lease IP configurations as DHCP does. Instead, a BOOTP server permanently assigns IP configurations to a BOOTP client. When a BOOTP client is started, the BOOTP server always assigns the same IP configurations to the BOOTP client. Hypertext Transfer Protocol (HTTP) is used to transfer Web pages on a TCP/IP network. Simple Mail Transfer Protocol (SMTP) is used to transfer e-mail messages on a TCP/IP network. SMTP is used to send e-mail, which Post Office Protocol 3 (POP3) is used to receive e-mail. Internet Printing Protocol (IPP) is used to enable network printing through a TCP/IP network such as the Internet. HTTP, SMTP and IPP are not used to automatically configure hosts on a TCP/IP network with IP settings. When using DHCP and dynamic addresses, clients can obtain different IP addresses when they reboot. If a computer's IP address changes when you reboot, you can deduce that it is using a dynamic address configuration.

You administer a TCP/IP network. You want to enable the hosts on your network to be automatically configured with IP configurations, such as IP address, subnet mask and default gateway address. The IP configurations should be leased to the clients for a limited period. Which protocol should you use to accomplish this task?

You should use Dynamic Host Configuration Protocol (DHCP) to automatically configure the hosts on your network with IP configurations. DHCP was designed to automatically configure frequently moved, fully boot-capable computers, such as laptop computers, with IP configurations. You can use DHCP to configure such IP settings as IP address, subnet mask, and default gateway address. Typically, DHCP information is leased to a client for a limited period. DHCP clients usually release DHCP information when they are shut down. When a DHCP client retrieves IP configurations from a DHCP server, the DHCP client does not necessarily have the same IP configurations that it was configured with on previous occasions. BOOTstrap Protocol (BOOTP) is a host configuration protocol that was designed before DHCP. BOOTP was designed to configure diskless workstations with IP configurations. BOOTP does not lease IP configuration as DHCP does. Instead, a BOOTP server permanently assigns IP configurations to a BOOTP client. When a BOOTP client is started, the BOOTP server always assigns the same IP configurations to the BOOTP client. Hypertext Transfer Protocol (HTTP) is used to transfer Web pages on a TCP/IP network. Simple Mail Transfer Protocol (SMTP) is used to transfer e-mail messages on a TCP/IP network. Internet Printing Protocol (IPP) is used to enable network printing through a TCP/IP network such as the Internet. HTTP, SMTP and IPP are not used to automatically configure hosts on a TCP/IP network with IP settings.

Your company has a network that consists of 12 computers on a single floor in your building. You need to set up a computer to work beyond the maximum length of an Ethernet segment. You have two Ethernet cables that will allow you to do this. You want to provide a connection only for this computer using an inexpensive device. Which device should you use?

You should use a repeater to connect the computer to the network. A repeater simply repeats the signal, extending the distance traveled by the signal. It is very inexpensive to purchase and implement. A switch is more expensive than a repeater. A switch is also more intelligent than a repeater, in that the switch directs the communication only to the receiving port instead of broadcasting to all ports. A bridge splits a larger network into two smaller networks. A bridge will not work in this scenario. A firewall is used to protect a network from unauthorized access. Firewalls are often expensive to implement. In addition, a firewall does not provide any sort of repeating function, as needed in this scenario.

You are wiring a small office for a client. The client has purchased several 568A and 568B wall jacks and enough 568A wiring cables to attach all devices correctly. You want to configure the network for ease of administration.

You should use only 568A wall jacks. Both the 568A and 568B wiring specifications will work for a network configuration. However, you must use the same specification throughout your network. Because the client has purchased enough 568A wiring cables to attach all devices correctly, you should choose to use the 568A wiring scheme. You should not use only the 568B wall jacks. Because the client has purchased 568A wiring cables, you should use wall jacks that use the 568A specification. You should not use both the 568A and 568B wall jacks. The same specification should be used throughout your network configuration. You should not purchase 568B wiring cables. You have 568A wiring cables that can be used. It is not necessary to purchase more cables.

Which connectors are used with fiber-optic cabling? (Choose two.)

he ST and SC connectors are the two most popular connectors available for fiber-optic cabling. Other common fiber-optic connectors are FC, FDDI, LC, D4, MU, MT, and MT-RJ. The following exhibit shows the four most used fiber optic connectors: An AUI connector is a 15-pin female connector that looks similar to the shape of the letter "D." It is also known as a DB-15 or Digital Intel Xerox (DIX) connector. It is typically a component of thick Ethernet (10Base5) connections, though it is being phased out with the introduction of Fast Ethernet. An RJ-11 connector is typically used to connect two pairs of UTP wiring to a voice-grade telephone system. RJ-45 connectors are used to connect unshielded twisted-pair (UTP) and shielded twisted-pair (STP) cable to hubs, switches, bridges, routers, network interface cards (NICs), and various other twisted-pair networking devices. RJ-45 connectors are shaped like RJ-11 connectors, only larger. They use an 8-pin connector housing eight (four pair) wires. Registered Jack (RJ) connectors use a small tab to lock the connector in place. The following exhibit shows an RJ-11 connector and an RJ-45 connector: Coaxial cables generally use either Bayonet Neill-Concilman (BNC) or Threaded Neill-Concilman (TNC) connectors. They can also use F connectors. The BNC connectors are shown in the following exhibit: The TNC connectors are shown in the following exhibit: The F connectors are shown in the following exhibit: