CCNA Vol. 1

Which of the following line subcommands tells a switch to wait until a show command's output has completed before displaying log messages on the screen? -exec-timeout 0 0 -history size 15 -no ip domain-lookup -logging synchronous

-logging synchronous Explanation: The logging synchronous line subcommand synchronizes the log message display with other command output so the log message does not interrupt a show command's output. The no ip domain-lookup command is not a line subcommand. The other two incorrect answers are line subcommands but do not configure the function listed in the question.

Which of the following are true about IP address 172.16.99.45's IP network? (Choose two answers.) -The network is a Class B network. -The number of host bits in the unsubnetted network is 16. -The network ID is 172.0.0.0. -The default mask for the network is 255.255.255.0. Select 2 answers

-The network is a Class B network. -The number of host bits in the unsubnetted network is 16. Explanation: The first octet (172) is in the range of values for Class B addresses (128-191). As a result, the network ID can be formed by copying the first two octets (172.16) and writing 0s for the last two octets (172.16.0.0). The default mask for all Class B networks is 255.255.0.0, and the number of host bits in all unsubnetted Class B networks is 16.

Examine the output of the show ipv6 interface brief command shown in the exhibit. What two address types are shown? -Anycast -Unique local -Multicast -Link-local Select 2 answers

-Unique local -Link-local Explanation: The output shows the link-local address, recognized based on its first digits of FE80. Similarly, the initial digits of FD identify the one Unique Local address. None of the addresses begin with FF, so none of the addresses listed in the output are multicast addresses. And none of the address begins with hex 2 or 3, or any other non-reserved values, so there are no Global Unicast addresses configured.

What is the purpose of the FCS field in an HDLC frame? -Identifies the destination L2 address for the frame -Used for identifying the type of L3 payload being carried in the frame -Used for error detection -Used to indicate to the receiving device that a new frame is arriving -Specifies the destination IP address for the frame

-Used for error detection The FCS field is used for error detection and is included as a trailer in the HDLC frame. The address field in the HDLC header indicates the Layer 2 destination address. The HDLC header and trailer information doesn't include the Layer 3 IP destination address (that is in the Layer 3 header information). The Type field in the HDLC header identifies the type of Layer 3 payload that is being encapsulated. A preamble is the concept of a recognizable bit pattern so that the receiving node will realize that a new frame is arriving. In HDLC, this is a field named Flag.

When the Cisco IOS CLI is initially accessed via console, Telnet, or SSH, with no extra privileges, which mode is the user placed into? -User mode -Enable mode -Configuration mode -Boot mode

-User mode Explanation: The two Cisco IOS exec modes are user mode and enable mode (privileged mode). When a device is initially accessed via console, Telnet, or SSH, users will be placed into user mode. They can enter into enable mode by using the enable command from within user mode.

An engineer needs to add a static IPv6 route for prefix 2000:1:2:3::/64 to Router R5 in the figure shown. Which of the following answers shows a valid static IPv6 route for that subnet on Router R5? -ipv6 route 2000:1:2:3::/64 FE80::FF:FE00:6 -ipv6 route 2000:1:2:3::/64 2000:1:2:56::6 -ipv6 route 2000:1:2:3::/64 2000:1:2:56::5 -ipv6 route 2000:1:2:3::/64 FE80::FF:FE00:5

-ipv6 route 2000:1:2:3::/64 2000:1:2:56::6 Explanation: All four answers show examples of commands that use a next-hop router IPv6 address. Two of the answers list R5's own IPv6 address (unicast or link-local), which is incorrect; the answer should be an address on the neighboring router, R6 in this case. For the two answers that list addresses on Router R6, the one that lists R6's global unicast address is correct. The one that lists R6's link-local address would also require R5's outgoing interface, so the answer that lists FE80::FF:FE00:6 would be rejected as well

Refer to the exhibit. Which of the following commands has been configured on the displayed switchport? Exhibit: -port disable -switchport shutdown -shutdown -disable

-shutdown Explanation: The Cisco IOS command that is used to control the state of an interface (switchport) is the shutdown/no shutdown command. By default, switchport interfaces are enabled, while router interfaces are disabled. This means that the shutdown command must have been configured on this interface (switchport) for it to be displayed as administratively disabled.

Which of the following are reserved private IP addresses, according to RFC 1918? -127.10.172.192 -169.254.128.222 -192.168.10.1 -172.29.42.167 -10.127.255.37 Select 3 answers

-192.168.10.1 -172.29.42.167 -10.127.255.37 Explanation: The RFC 1918 private network numbers are 10.0.0.0, Class Bs between 172.16.0.0 and 172.31.0.0 (inclusive), and all Class C networks that begin with 192.168. All addresses beginning with 127 are reserved, but not as valid private IP addresses.

If a WLC is positioned so that it connects into or near the core layer of a network, which type of wireless architecture is implied? -A centralized architecture -An autonomous architecture -An embedded architecture -A mobility express architecture

-A centralized architecture Explanation: If the WLC is positioned near the core or center of the network, a centralized or unified deployment has been used. An autonomous architecture is not correct because it would not require a WLC at all. An embedded architecture has a WLC that is embedded within a network switch, usually in the access layer. Mobility express positions the WLC function within the actual APs.

What is true when two OSPF routers both reach the two-way state of their neighbor relationship? -Each router sees its Router ID in the hello packet sent by the neighboring router -The routers succeeded in pinging each other -The routers exchanged their LSDBs -The routers are neighbors and are ready to exchange their LSDBs -The routers exchanged Hellos and all necessary parameters match Select 3 answers

-Each router sees its Router ID in the hello packet sent by the neighboring router -The routers are neighbors and are ready to exchange their LSDBs -The routers exchanged Hellos and all necessary parameters match Explanation: A two-way state will be reached after several steps. The routers will both send Hellos, check parameters, and if the parameters match, list the neighbor's RID in subsequent Hellos. At that point, both reach a 2-way state and are ready to exchange their LSDBs. Note that OSPF does not use ping as any part of establishing a neighbor relationship. Also, note that if the routers had begun to exchange their LSDBs, they would have reached other OSPF neighbor states.

In which of the following modes of the CLI could you configure the duplex setting for interface Fast Ethernet 0/5? -VLAN mode -User mode -Enable mode -Global configuration mode -Interface configuration mode

-Interface configuration mode Explanation: Cisco switches can be configured for speed (with the speed command) and duplex (with the duplex command) in interface configuration mode.

Which one of the following is used to protect the integrity of data in a wireless frame? -WIPS -WEP -MIC -EAP

-MIC Explanation: A message integrity check (MIC) is an effective way to protect against data tampering. WIPS is not correct because it provides intrusion protection functions. WEP is not correct because it does not provide data integrity along with its weak encryption. EAP is not correct because it defines the framework for authentication.

Review the topology diagram. Network 10.123.0.0/24 is the backbone area. Network 10.12.0.0/24 is area 1, and network 10.34.0.0/29 is in area 2. Which of the following are true? -R3 would see the OSPF network of 10.12.0.0/24 as an intra-area route. -R1 is a backbone router. -R1 is an internal router. -R1 is an ABR. -R1 and R3 would have the same LSA information about the backbone area. Select 3 answers

-R1 is a backbone router. -R1 is an ABR. -R1 and R3 would have the same LSA information about the backbone area. Explanation: First, consider R1. R1 connects to both the backbone area and another non-backbone area, so it is an Area Border Router (ABR). Because R1 has at least one interface connected to the backbone area, R1 serves as a backbone router. Those facts reveal two correct answers. However, R1 does not act as an internal router because internal routers connect to only one area, which makes one answer incorrect. Two answers describe the OSPF database entries and routes learned by R3. First, both R1 and R3 connect to the backbone area. All routers connecting to the same area will learn identical OSPF database entries (LSAs) as all other routers in the area, making one additional answer correct. Finally, one answer claims R3 would see a route to 10.12.0.0/24 from a remote non-backbone area as an intra-area route, which is incorrect. To be seen as an intra-area route, R3 would need to have at least one interface connected to that area, and it does not.

Which of these terms refers to a name that wireless devices use to advertise a wireless network? -Repeater -SSID -AP -Channel

-SSID Explanation: The answers: - SSID: (Service Set Identifier) is a name of a Wi-Fi network that is advertised. Wireless devices can then join that Wi-Fi network. - Repeater: A type of device that extends wireless coverage - AP: (Access Point) has a wired connection to the LAN and also communicates with wireless devices. - Channel: Refers to frequencies that can be used to communicate over the Wi-Fi network. Sometimes you need to change the channel because there might be too much interference, or it is too busy.

The process of TCP on one computer marking a TCP segment as segment 1, and the receiving computer then acknowledging the receipt of TCP segment 1 is an example of what? -OSI model -Data encapsulation -Adjacent-layer interaction -Same-layer interaction -All of these answers are correct.

-Same-layer interaction Explanation: Same-layer interaction occurs on multiple computers. The functions defined by that layer typically need to be accomplished by multiple computers—for example, the sender setting a sequence number for a segment and the receiver acknowledging receipt of that segment. A single layer defines that process, but the implementation of that layer on multiple devices is required to accomplish the function.

Refer to the network topology diagram in the exhibit; then choose which of the following statements about the network access layer are correct. -The access layer is part of the BSS. -The APs connect to the access layer with access links. -The access layer is part of the ESS. -The access layer hosts an embedded WLC deployment -The APs connect to the access layer with trunk links. -The access layer hosts a centralized WLC deployment

-The APs connect to the access layer with access links. -The access layer is part of the ESS. -The access layer hosts an embedded WLC deployment Explanation: The diagram shows an embedded WLC deployment because the controllers are located in the access layer switches. The APs are lightweight, so each one connects to the access layer with an access link. Trunk links are not used because CAPWAP tunnels take care of transporting traffic across multiple VLANs between the APs and the WLC. The access layer is part of the ESS because it provides connectivity between APs. It is not part of the BSS because each AP provides its own set of wireless BSSs to wireless users that are within range.

Suppose an AP is connected to an access layer switch in a network infrastructure. The WLC also exists in the same access layer switch. The AP and WLC work together to provide a functional wireless service, which is configured with four WLANs for various client devices to use. Which of the following statements are correct? -The WLC is part of a Mobility Express deployment. -The WLC is part of an embedded deployment. -The AP will advertise one unique BSSID for all WLANs. -The AP and WLC form an autonomous architecture. -The AP and WLC form a split-MAC architecture. -The AP will advertise four unique BSSIDs, one for each WLAN. Select 3 answers

-The WLC is part of an embedded deployment. -The AP and WLC form a split-MAC architecture. -The AP will advertise four unique BSSIDs, one for each WLAN Explanation: The AP and WLC form a split-MAC architecture, dividing the traditional AP functions between themselves. Because the WLC exists at the access layer switch, it is most likely part of an embedded controller deployment. As such, WLCs are located within each access layer switch, rather than at a central location, in a cloud location, or within an AP. The AP will advertise one unique BSSID for each WLAN that it is configured to provide.

Which of the following are private IP networks? (Choose two answers.) -192.1.168.0 -172.32.0.0 -172.31.0.0 -11.0.0.0 -192.168.255.0 Select 2 answers

-172.31.0.0 -192.168.255.0 Explanation: The private IPv4 networks, defined by RFC 1918, are Class A network 10.0.0.0, the 16 Class B networks from 172.16.0.0 to 172.31.0.0, and the 256 Class C networks that begin with 192.168.

Which of the following masks, when used as the only mask within a Class B network, would supply enough subnet bits to support 100 subnets? (Choose two.) -255.255.252.0 -/24 -/20 -255.255.255.252 Select 2 answers

-/24 -255.255.255.252 Explanation: The masks in binary define a number of binary 1s, and the number of binary 1s defines the length of the prefix (network + subnet) part. With a Class B network, the network part is 16 bits. To support 100 subnets, the subnet part must be at least 7 bits long. Six subnet bits would supply only 2^6 = 64 subnets, while 7 subnet bits supply 2^7 = 128 subnets. The /24 answer supplies 8 subnet bits, and the 255.255.255.252 answer supplies 14 subnet bits.

A fellow engineer tells you to configure the DHCP server to lease the last 100 usable IP addresses in subnet 10.1.4.0/23. Which of the following IP addresses could be leased as a result of your new configuration? -10.1.4.254 -10.1.7.200 -10.1.255.200 -10.1.4.156 -10.1.5.220

-10.1.5.220 Explanation: To answer this question, you need to find the range of addresses in the subnet, which typically then means you need to calculate the subnet ID and subnet broadcast address. With a subnet ID/mask of 10.1.4.0/23, the mask converts to 255.255.254.0. To find the subnet broadcast address, following the decimal process described in this chapter, you can copy the subnet ID's first two octets because the mask's value is 255 in each octet. You write a 255 in the fourth octet because the mask has a 0 on the fourth octet. In octet 3, the interesting octet, add the magic number (2) to the subnet ID's value (4), minus 1, for a value of 2 + 4 - 1 = 5. (The magic number in this case is calculated as 256 - 254 = 2.) That makes the broadcast address 10.1.5.255. The last usable address is 1 less: 10.1.5.254. The range that includes the last 100 addresses is 10.1.5.155 - 10.1.5.254.

Which of the following is the resident subnet ID for IP address 10.7.99.133/24? -10.7.99.0 -10.7.99.128 -10.7.0.0 -10.0.0.0

-10.7.99.0 Explanation: The mask converts to 255.255.255.0. To find the subnet ID, for each octet of the mask that is 255, you can copy the IP address's corresponding values. For mask octets of decimal 0, you can record a 0 in that octet of the subnet ID. As such, copy the 10.7.99 and write a 0 for the fourth octet, for a subnet ID of 10.7.99.0.

Which of the following Ethernet standards defines Gigabit Ethernet over UTP cabling? 100BASE-T 1000BASE-T None of the other answers is correct. 10GBASE-T

-1000BASE-T Explanation: The number before the word BASE defines the speed, in megabits per second (Mbps). 1000 Mbps equals 1 gigabit per second (1 Gbps). The T in the suffix implies twisted-pair or UTP cabling, so 1000BASE-T is the UTP-based Gigabit Ethernet standard name.

Which of the following IP address/mask combinations, if configured on a working router interface, would create a connected route for an entire classful network, instead of a route for a subnet of a classful network? -172.16.8.1/22 -172.16.1.1/16 -10.2.2.2/28 -192.168.1.1/24 -172.16.4.3/24 -10.1.1.1/16 Select 2 answers

-172.16.1.1/16 -192.168.1.1/24 Explanation: Any valid unicast IP address/mask combination, when configured on a router interface, if the interface is up, will cause the router to create a connected route. That route will be for the group defined by the IP address/mask, whether it be a subnet of a classful network, or a subnet. To define an entire classful network, the mask must be the default mask for the network class of the address. Two answers list class A addresses that begin with 10; neither uses the default class A mask /8, so neither creates a route for the entire classful network. The answer with 172.16.1.1/16 uses the default mask for class B (/16), so it would create a route for entire classful network 172.16.0.0. Similarly, the answer showing 192.168.1.1/24 uses the default mask for class C networks, and would create a route for classful network 192.168.1.0.

Which of the following is a network broadcast address? -192.168.255.1 -172.30.255.255 -224.1.1.255 -10.1.255.255

-172.30.255.255 Explanation: To find the network broadcast address, first determine the class, and then determine the number of host octets. At that point, convert the host octets to 255 to create the network broadcast address. In this case, 10.1.255.255 is in a Class A network, with the last three octets as host octets, for a network broadcast address of 10.255.255.255. For 192.168.255.1, it is a Class C address, with the last octet as the host part, for a network broadcast address of 192.168.255.255. Address 224.1.1.255 is a Class D address, so it is not in any unicast IP network and the question does not apply. For 172.30.255.255, it is a Class B address, with the last two octets as host octets, so the network broadcast address is 172.30.255.255.

Which options are stable OSPF neighbor states? -Established -Exstart -Loading -2-way -Full Select 2 answers

-2-way -Full Explanation: There are two stable OSPF states: 2-way and full. If the link is not a type that uses DR/BDRs, then the only stable state would be full, but if the link type uses DR/BDRs, then it is possible for routers to exist in the 2-way state and be stable because they are available to be the BDR but are not currently the DR or BDR on a link. Of the incorrect answers, Exstart and Loading are correct OSPF neighbor states, but are interim states. Established is not an OSPF state (but is the correct stable state for eBGP.)

Which of the following is the prefix for address -2000:0000:0000:0005:6000:0700:0080:0009, assuming a mask of /64? -2000:0:0:5:0:0:0:0/64 -2000::5:0:0:0:0/64 -2000:0:0:5::/64 -2000::5::/64

-2000:0:0:5::/64 Explanation: The /64 prefix length means that the last 64 bits, or last 16 digits, of the address should be changed to all 0s. That process leaves the unabbreviated prefix as 2000:0000:0000:0005:0000:0000:0000:0000. The last four quartets are all 0s, making that string of all 0s be the longest and best string of 0s to replace with ::. After removing the leading 0s in other quartets, the answer is 2000:0:0:5::/64.

Consider the exhibit. Assuming a standard prefix length of /64, what IPv6 connected route would exist when the show ipv6 route command is entered? Exhibit { R1#show ipv6 interface brief FastEthernet0/0 [up/up] FE80::C801:1AFF:FEE0:8 2500:3D5B:1000:573B:3492:A4B1:78:3A0 FastEthernet0/1 [administratively down/down] unassigned Ethernet1/0 [up/up] unassigned Ethernet1/1 [up/up] unassigned Ethernet1/2 [up/up] unassigned Ethernet1/3 [administratively down/down] unassigned R1# } -2500:3d5b::/64 -2500:3d5b:1000::/64 -2500:3d5b:1000:573b::/64 -2500:3d5b:1000:573b:3492::/64

-2500:3d5b:1000:573b::/64 Explanation: An IPv6 address is 128 bits in length, which, when converted to hex, equals 32 hex characters. To find the correct route that would exist in the routing table, you must split the 2500:3d5b:1000:573b:3492:a4b1:0078:03a0 address in half, leaving 64 bits, or 16 hex characters. This gives the subnet of 2500:3d5b:1000:573b::/64.

Which of the following answers lists the dotted-decimal notation (DDN) equivalent of /30? -255.255.254.0 -255.255.255.192 -255.255.255.0 -255.255.255.252 -255.255.255.240

-255.255.255.252 Explanation: /30 is the equivalent of the mask that in binary has 30 binary 1s. To convert that to DDN format, write down all the binary 1s (30 in this case), followed by binary 0s for the remainder of the 32-bit mask. Then take 8 bits at a time and convert from binary to decimal (or memorize the nine possible DDN mask octet values and their binary equivalents). Using the /30 mask in this question, the binary mask is 11111111 11111111 11111111 11111100. Each of the first three octets is all binary 1s, so each converts to 255. The last octet, 11111100, converts to 252, for a DDN mask of 255.255.255.252. See Appendix A, "Numeric Reference Tables," for a decimal/binary conversion table.

Refer to the diagram and exhibit; what is the metric for the current best path through the network from R1 to host D? Exhibit -20 -41 -30 -32

-32 Explanation: The current path through the network from R1 to host D is from R1 to R3 to R4 to host D. To trace this, you need to look at the lowest OSPF cost through the entire network (remember that OSPF is a link-state protocol and uses a complete picture of the network to make routing decisions). There are five main potential paths from R1 to host D: R1 -> R4 R1 -> R2 -> R4 R1 -> R3 -> R4 R1 -> R2 -> R3 -> R4 R1 -> R3 -> R2 -> R4 As for costs: The first path has a cost of 110 (R1's F1/0, R4's F1/1) The second path has a cost of 41 (R1's F0/0, R2's F1/0, and R4's F1/1) The third path has a cost of 32 (R1's F0/1, R3's F1/0, and R4's F1/1) The fourth path has a cost of 45 (R1's F0/0, R2's F0/1, R3's F1/0, and R4's F1/1) The fifth path has a cost of 52 (R1's F0/1, R3's F0/1, R2's F1/0, and R4's F1/1). The lowest path has a cost of 32.

PC A sends a frame with source MAC address 0200.AAAA.AAAA and destination MAC address 0200.DDDD.DDDD. The frame arrives at switch SW1. Predict the interfaces in the diagram out which the three switches will forward copies of the frame. Out how many interfaces will the three switches collectively forward a copy of this frame? -6 -3 -2 -5 -1 -4

-5 Explanation: When SW1 receives the frame on its Fa0/1 interface, SW1 checks to see if the interface is an access VLAN or not. Per the show interfaces status command output in the exhibit, the interface is in VLAN 2, and not trunking, so SW1 only forwards the frame in VLAN 2. Because the destination MAC address is not listed in SW1's MAC address table as being in VLAN 2, SW1 floods the frame. However, SW1 will not forward the frame back out Fa0/1, and SW1 will not forward the frame out its Fa0/2 interface, because that interface is an access interface in VLAN 3 (again per the show interfaces status command output). So, SW1 only forwards the frame out its trunking interface, Gi0/1, connected to SW2. SW2 determines the VLAN ID based on the trunking header in the received frame, which will list VLAN 2. SW2 will not forward the frame back out Gi0/2. SW2's show interfaces status command implies that its Fa0/3 interface is in VLAN 3, and that Fa0/4 is in VLAN 2, and that Gi0/1 is a trunk. Because the destination MAC is not in SW2's MAC address table for VLAN 2, SW2 floods the frame in VLAN 2, forwarding the frame out its Fa0/4 and Gi0/1 interfaces. Finally, SW3 determines the VLAN per the trunking header on the received frame. SW3's output for the show interfaces status command, as well as the show mac address-table output, confirms that SW3's Fa0/5 and Fa0/6 interfaces are working and in VLAN 2. SW3 does not list the destination MAC (0200.dddd.dddd) in its MAC address table in VLAN 2, so SW3 floods the frame, forwarding it out Fa0/5 and Fa0/6. So, the three switches collectively forward the frame out a total of 5 interfaces.

If your ISP assigns you prefix 2003:1234:abcd:6600:: /56, how many bits do you have to create your subnets? -12 bits -8 bits -4 bits -16 bits

-8 bits Explanation: An IPv6 address is 128 bits—64 bits are assigned for the interface ID and the other 64 bits are assigned for the prefix. The ISP will give you a prefix, and the rest of the bits will determine how many bits you have left to assign a subnet (64 - amount of bits in the prefix). In this example, you received a 56-bit prefix, which means you have 8 bits left to assign a subnet.

Which of the following protocols are examples of TCP/IP data-link layer protocols? (Choose two answers.) -802.11 -IP -HTTP -SMTP -UDP -TCP -Ethernet

-802.11 -Ethernet Explanation: Of the incorrect answers, IP is a network layer protocol, TCP and UDP are transport layer protocols, and SMTP and HTTP are application layer protocols.

The diagram shows a simple internetwork in which all the LAN connections use FastEthernet. Select the answers that list the correct cable types -An Ethernet crossover cable between SW3 and Hub1 -A rollover cable between SW3 and AP1 -An Ethernet crossover cable between SW1 and R1 -A crossover cable between SW1 and SW2

-An Ethernet crossover cable between SW3 and Hub1 -A crossover cable between SW1 and SW2 Explanation: A crossover cable is needed between two devices that transmit on the same wire pair, and a straight-through cable is needed for devices that transmit on opposite wire pairs. For the listed answers, SW1 uses the opposite pairs from router R1, so they use a straight-through cable. SW3 and Hub 1 transmit on the same wire pair, requiring a crossover cable. SW3 and AP1 use opposite pairs, so they need a straight-through cable. Finally, SW1 and SW2 use the same pair, so a crossover cable is needed.

A LAN design uses a Layer 3 EtherChannel between two switches SW1 and SW2, with port-channel interface 1 used on both switches. SW1 uses ports G0/1 and G0/2 in the channel. However, only interface G0/1 is bundled into the channel and working. Think about the configuration settings on port G0/2 that could have existed before adding G0/2 to the EtherChannel. Which answers identify a setting that could prevent IOS from adding G0/2 to the Layer 3 EtherChannel? (Choose two answers.) -A different speed (speed value) -A different access VLAN (switchport access vlan vlan-id) -A default setting for switchport (switchport) -A different STP cost (spanning-tree cost value)

-A different speed (speed value) -A default setting for switchport (switchport) Explanation: With a Layer 3 EtherChannel, two configuration settings must be the same on all the physical ports, specifically the speed and duplex as set with the speed and duplex commands. Additionally, the physical ports and port-channel port must all have the no switchport command configured to make each act as a routed port. So, having a different speed setting, or being configured with switchport rather than no switchport, would prevent IOS from adding interface G0/2 to the Layer 3 EtherChannel. As for the wrong answers, both have to do with Layer 2 configuration settings. Once Layer 2 operations have been disabled because of the no switchport command, those settings related to Layer 2 that could cause problems on Layer 2 EtherChannels do not then cause problems for the Layer 3 EtherChannel. So, Layer 2 settings about access VLANs, trunking allowed lists, and STP settings, which must match before an interface can be added to a Layer 2 EtherChannel, do not matter for a Layer 3 EtherChannel.

The figure shows an internetwork, with IP addresses and default gateways for some devices. The addresses have been configured on the routers, and the PCs have been configured using the same subnet masks as the routers on the LANs. A routing protocol has been enabled, and both routers have learned all routes known by the other router. Which of the following statements are true about the behavior of IP in this network? -With 2 IP addresses assigned, R3's LAN subnet allows for 14 additional IP addresses to be assigned. -With 2 IP addresses assigned, R3's LAN subnet allows for 30 additional IP addresses to be assigned. -A new PC added to the R1 LAN could be assigned IP address 10.4.4.255/23, default gateway 10.4.4.200, and be able to ping PC3. -A new PC added to the R1 LAN could be assigned IP address 10.4.5.255/23, default gateway 10.4.4.200, and be able to ping PC3.

-A new PC added to the R1 LAN could be assigned IP address 10.4.4.255/23, default gateway 10.4.4.200, and be able to ping PC3. Explanation: On the R3 LAN, the prefix of /28 implies a mask of 255.255.255.240 and 4 host bits. The formula for the number of hosts in a subnet is 2^4, minus 2, or a total of 14 hosts. With two host IP addresses already assigned, only 12 remain available for assignment. The R1 LAN subnet uses a prefix of /23, which implies a mask of 255.255.254.0, and 9 host bits. The formula for the number of hosts in a subnet is 2^9, minus 2, or a total of 510 hosts. The R1 LAN has a subnet number of 10.4.4.0 and a range of valid addresses of 10.4.4.1 through 10.4.5.254, with a subnet broadcast address of 10.4.5.255. Note that odd-looking addresses 10.4.4.255 and 10.4.5.0 are inside the range of valid IP addresses.

Which one of the following is not needed for a lightweight AP in default local mode to be able to support three SSIDs that are bound to three VLANs? -A CAPWAP tunnel to a WLC -An access link bound to a single VLAN -A WLC connected to three VLANs -A trunk link carrying three VLANs

-A trunk link carrying three VLANs Explanation: A trunk link carrying three VLANs is not needed at all. A lightweight AP in local mode needs only an access link with a single VLAN; everything else is carried over the CAPWAP tunnel to a WLC. The WLC will need to be connected to three VLANs so that it can work with the LAP to bind them to the three SSIDs.

In the figure, PC1 is in VLAN 1, PC6 is in VLAN 5, and R1 is using 802.1Q trunking and the default native VLAN. R1 has an IP address associated with both VLAN 1 and VLAN 5, as shown. When you consider only the traffic that flows in both directions between PC1 and PC6 and no other traffic in the network, which of the following is true? -Frames that SW1 forwards out fa0/1 to PC1 have a VLAN 1 tag in front of the normal Ethernet header. -After SW1 receives a frame from PC1, SW1 forwards the frame out fa0/22 to R1. This forwarded frame has a VLAN 1 tag in the Ethernet header as it exits SW1's fa0/22 interface. -Frames that SW1 forwards out fa0/6 to PC6 have a VLAN 5 tag in front of the normal Ethernet header. -After SW1 receives a frame from PC6, SW1 forwards the frame out fa0/22 to R1. This forwarded frame has a VLAN 5 tag in the Ethernet header as it exits SW1's fa0/22 interface

-After SW1 receives a frame from PC6, SW1 forwards the frame out fa0/22 to R1. This forwarded frame has a VLAN 5 tag in the Ethernet header as it exits SW1's fa0/22 interface Explanation: The interfaces that are connected to PC1 and PC6 do not use trunking, so a VLAN tag would never be in the normal Ethernet header. With 802.1Q, VLAN 1 is the native VLAN by default; therefore, no VLAN tag is used. The only frames that have VLAN tags in this case are those in VLAN 5, as they pass between R1 and the switch.

The IP addresses are correctly configured and all interfaces shown are up/up. Which of the following is required for a host on 10.1.1.0/24 to ping a host on 10.1.3.0/24? -Albuquerque: ip route 10.1.3.0 255.255.255.0 10.1.130.253 Seville: ip route 10.1.1.0 255.255.255.0 10.1.129.252 Yosemite: ip route 10.1.1.0 255.255.255.0 10.1.129.253 ip route 10.1.3.0 255.255.255.0 10.1.129.253 -Albuquerque: ip route 10.1.3.0 255.255.255.0 10.1.128.252 Seville: ip route 10.1.1.0 255.255.255.0 10.1.129.252 Yosemite: ip route 10.1.1.0 255.255.255.0 10.1.128.251 ip route 10.1.3.0 255.255.255.0 10.1.129.253 -Albuquerque: ip route 10.1.1.0 255.255.255.0 10.1.128.252 Seville: ip route 10.1.3.0 255.255.255.0 10.1.129.252 Yosemite: ip route 10.1.3.0 255.255.255.0 10.1.128.251 ip route 10.1.1.0 255.255.255.0 10.1.129.253 -Albuquerque: ip route 10.1.3.0 255.255.255.0 10.1.128.252 Seville: ip route 10.1.1.0 255.255.255.0 10.1.129.252 Yosemite: ip route 10.1.1.0 255.255.255.0 10.1.129.253 ip route 10.1.3.0 255.255.255.0 10.1.128.251

-Albuquerque: ip route 10.1.3.0 255.255.255.0 10.1.128.252 Seville: ip route 10.1.1.0 255.255.255.0 10.1.129.252 Yosemite: ip route 10.1.1.0 255.255.255.0 10.1.128.251 ip route 10.1.3.0 255.255.255.0 10.1.129.253 Explanation: Even though it is not the optimal path, the solution where Yosemite correctly knows how to reach 10.1.3.0/24 and 10.1.1.0/24, and Albuquerque and Seville both use Yosemite as their next hop router, is the only workable solution from the choices given. All the other options do not provide enough accurate routing information to forward packets between 10.1.1.0/24 and 10.1.3.0/24.

Which of the following rules does an OSPF router follow with regard to the selection of a router ID when the OSPF process starts? -An administratively configured router ID is used as the first choice. -The default router ID is the loopback address of 127.0.0.1. -If no configured IPv4 addresses exist, and if there is no configured router ID, the router creates and uses a randomly generated ID, and uses that until either an IPv4 address is configured or until a router ID is configured. -In the absence of a specified router ID, the highest IP on a loopback is used. -The highest IP on a nonloopback interface is the last choice for use as router ID in OSPF. Select 3 answers

-An administratively configured router ID is used as the first choice. -In the absence of a specified router ID, the highest IP on a loopback is used. -The highest IP on a nonloopback interface is the last choice for use as router ID in OSPF. Explanation: The selection order for the 32-bit OSPFv2 router ID, in order of priority, is: 1. Configured router ID 2. Highest IPv4 address on a working loopback interface 3. Highest IPv4 address on any other working interface The OSPF process will not start without a router ID, and in the absence of the three methods listed in the explanation, the router will not use the logical IPv4 loopback address of 127.0.0.1.

An access point is set up to offer wireless coverage in an office. Which one of the following is the correct 802.11 term for the resulting standalone network? -IBSS -BSS -BSA -BSD

-BSS Explanation: An AP offers a basic service set (BSS). BSA is incorrect because it is a Basic Service Area, or the cell footprint of a BSS. BSD is incorrect because it does not pertain to wireless at all. IBSS is incorrect because it is an Independent BSS, or an ad hoc network, where an AP or BSS is not needed at all.

Which one of the following is used to uniquely identify an AP and the basic service set it maintains with its associated wireless clients? -Ethernet MAC address -BSSID -Radio MAC address -SSID

-BSSID Explanation: The AP at the heart of a BSS or cell identifies itself (and the BSS) with a Basic Service Set Identifier (BSSID). It also uses an SSID to identify the wireless network, but that is not unique to the AP or BSS. Finally, the radio MAC address is used as the basis for the BSSID value, but the value can be altered to form the BSSID for each SSID that the AP supports.

An engineer connects routers R13 and R14 to the same Ethernet LAN and configures them to use OSPFv2. Which answers describe a combination of settings that would prevent the two routers from becoming OSPF neighbors? -Both routers' interface IP addresses reside in the same subnet. -Both routers' OSPF process uses router ID 13.13.13.13. -Both routers' interfaces use an OSPF Dead interval of 40. -Both routers' OSPF process uses process ID 13.

-Both routers' OSPF process uses router ID 13.13.13.13. Explanation: As worded, the correct answers should be a scenario that would prevent the neighbor relationship. The answers all list values that are identical or similar on the two routers. Of those, the use of an identical OSPF router ID (RID) on the two routers prevents them from becoming neighbors, making that one answer correct. Of the incorrect answers, both routers must have the same Dead interval, so both using a Dead interval of 40 causes no issues. The two routers can use any OSPF process ID (the same or different value, it does not matter), making that answer incorrect. Finally, the two routers' IP addresses must be in the same subnet, so again that scenario does not prevent R13 and R14 from becoming neighbors.

The figure shows a network in which IPv6 will be implemented on all interfaces. The exhibit shows some details about the current IPv6 operations on router R1's two LAN interfaces, G0/1 and G0/2. What is true about the IPv6 status and configuration on those two interfaces? Exhibit { R1#show ipv6 int g0/1 GigabitEthernet0/1 is up, line protocol is up IPv6 is enabled, link-local address is FE80::11FF:FE11:1111 No Virtual link-local address(es): No global unicast address is configured Joined group address(es): FF02::1 FF02::2 FF02::1:FF11:1111 ! lines omitted for brevity R1#show ipv6 int g0/2 GigabitEthernet0/2 is up, line protocol is up IPv6 is enabled, link-local address is FE80::44FF:FE44:4444 No Virtual link-local address(es): Global unicast address(es): 2001:DB8:1:33::1, subnet is 2001:DB8:1:33::/64 Joined group address(es): FF02::1 FF02::2 FF02::5 FF02::6 FF02::1:FF00:1 FF02::1:FF44:4444 ! lines omitted for brevity } -Both support the all-IPv6-hosts multicast address. -Both support the all-IPv6-routers multicast address. -Both interfaces have two solicited node multicast addresses. -Both support the all-OSPF-routers multicast address. -One of the interfaces cannot forward IPv6 packets. Select 2 answers

-Both support the all-IPv6-hosts multicast address. -Both support the all-IPv6-routers multicast address. Explanation: Of the two correct answers, one references the all-IPv6-hosts multicast address, which is FF02::1, and the other references the all-IPv6 routers multicast address, FF02::2. The exhibit lists both addresses as being used by both interfaces, making those answers correct. Only one interface (G0/2) lists two multicast addresses used by OSPF: FF02::5 (the all OSPF routers multicast address) and FF02::6 (the all-DR-routers multicast address). That fact makes incorrect the answer that claims that both interfaces support OSPF. Solicited node multicast addresses begin with FF02::1:FF, with six additional hex digits. Examining the output, interface G0/1 has just one solicited node multicast address, while G0/2 has two. Note that each interface has one of these multicast addresses to match each unicast address that has a unique last six hex digits, and in this case, interface G0/1 has only a link local address, while G0/2 has its link local address and global unicast address. Note that G0/2's link local and global unicast addresses end with different values in the last six hex digits, so it has two solicited node multicast addresses. Finally, one answer suggested that one of the two interfaces is not ready to route packets. Note that on the second line of output for each interface, it mentions that IPv6 is enabled and that both have a link local address. So both interfaces are prepared to receive and forward IPv6 packets.

An engineer configures a switch to put interfaces G0/1 and G0/2 into the same Layer 2 EtherChannel. Which of the following terms is used in the configuration commands? -EtherChannel -PortChannel -Channel-group -Ethernet-Channel

-Channel-group Explanation: IOS uses the channel-group configuration command to create an EtherChannel. Then the term etherchannel is used in the show etherchannel command, which displays the status of the channel. The output of this show command then names the channel a PortChannel. The only answer that is not used somewhere in IOS to describe this multilink channel is Ethernet-Channel.

What are common LAN Layer 1 problem indicators? -Incorrect IP addressing -High-bandwidth utilization -Collisions -Incorrect VLAN assignments -Late collisions Select 2 answers

-Collisions -Late collisions Explanation: Collisions and late collisions can be due to mismatched settings such as duplex on either side of the connection. A late collision in a half-duplex environment could be due to physical cable lengths being longer than the standard permits. High-bandwidth utilization could be normal, based on the amount of traffic flowing through the network. Incorrect IP addressing would be a symptom of poor Layer 3 planning and implementation, and incorrect VLAN assignments would be poor Layer 2 implementation and/or planning.

Which of the following installation steps are more likely required on a Cisco router, but not typically required on a Cisco switch? (Choose two answers.) -Connect to the console port -Connect Ethernet cables -Connect serial cables -Turn the on/off switch to "on" -Connect the power cable Select 2 answers

-Connect serial cables -Turn the on/off switch to "on" Explanation: Cisco routers have an on/off switch, but Cisco switches generally do not.

What does CAPWAP mean? -Control and Policing of Wireless Access Points -Configuring and Policing of Wireless Access Points -Configuring and Provisioning of Wireless Access Points -Control and Provisioning of Wireless Access Points

-Control and Provisioning of Wireless Access Points

A company implements a TCP/IP network, with PC1 sitting on an Ethernet LAN. Which of the following protocols and features requires PC1 to learn information from some other server device? -None of these answers is correct. -DNS -ARP -ping

-DNS Explanation: Address Resolution Protocol (ARP) does allow PC1 to learn information, but the information is not stored on a server. The ping command does let the user at PC1 learn whether packets can flow in the network, but it again does not use a server. With the Domain Name System (DNS), PC1 acts as a DNS client, relying on a DNS server to respond with information about the IP addresses that match a given hostname.

The process of a web server adding a TCP header to the contents of a web page, followed by adding an IP header and then adding a data-link header and trailer, is an example of what? -All of these answers are correct -Same-layer interaction -Data Encapsulation -OSI Model

-Data Encapsulation Explanation: Encapsulation is defined as the process of adding a header in front of data supplied by a higher layer (and possibly adding a trailer as well).

Which one of the following controller interfaces maps a WLAN to a VLAN? -Dynamic interface -WLAN interface -Virtual interface -Bridge interface

-Dynamic interface Explanation: A dynamic interface makes a logical connection between a WLAN and a VLAN, all internal to the controller.

What are the two ICMP messages used by the ping command? -Timestamp and timestamp reply -Echo request and echo reply -Time exceeded and destination unreachable -Router advertisement and router solicitation

-Echo request and echo reply Explanation: - Internet Control Message Protocol (ICMP) is used by network devices to send error and informational messages to the sending device. - The ping command uses ICMP echo request and ICMP echo reply. The source sends an echo-request and expects and echo-reply from the destination. - Router advertisement and router solicitation are used for IPv6 auto-configuration. - Timestamp and timestamp reply are used for time synchronization. Time exceeded and destination unreachable is to notify the sending device that the TTL (time-to-live) has reached zero.

Router R1 currently supports IPv4, routing packets in and out all its interfaces. R1's configuration needs to be migrated to support dual-stack operation, routing both IPv4 and IPv6. Which of the following tasks must be performed before the router can also support routing IPv6 packets? (Choose two answers.) -Enable support for both versions with the ip versions 4 6 global command. -Enable IPv6 on each interface using an ipv6 address interface subcommand. -Additionally enable IPv6 routing using the ipv6 unicast-routing global command. -Migrate to dual-stack routing using the ip routing dual-stack global command. Select 2 answers

-Enable IPv6 on each interface using an ipv6 address interface subcommand. -Additionally enable IPv6 routing using the ipv6 unicast-routing global command. Explanation: Of the four answers, the two correct answers show the minimal required configuration to support IPv6 on a Cisco router: enabling IPv6 routing (ipv6 unicast-routing) and enabling IPv6 on each interface, typically by adding a unicast address to each interface (ipv6 address...). The two incorrect answers list nonexistent commands.

Router R1 has an interface named Gigabit Ethernet 0/1, whose MAC address has been set to 0200.0001.000A. The interface is then configured with the ipv6 address 2001:1:1:1:200:FF:FE01:B/64 interface subcommand; no other ipv6 address commands are configured on the interface. Which of the following answers lists the link-local address used on the interface? -FE80::FF:FE01:A -FE80::200:FF:FE01:B -FE80::FF:FE01:B -FE80::200:FF:FE01:A

-FE80::FF:FE01:A Explanation: With an ipv6 address command configured for a global unicast address, but without a link-local address configured with an ipv6 address command, the router calculates its link-local address on the interface based on its MAC address and EUI-64 rules. The universal global unicast IPv6 address is NOT used. The first half of the link-local address begins FE80:0000:0000:0000. The router then calculates the second half of the link-local address value by taking the MAC address (0200.0001.000A), injecting FF FE in the middle (0200.00FF.FE01.000A), and flipping the seventh bit (0000.00FF.FE01.000A).

Which of the following RSTP port states have the same name and purpose as a port state in traditional STP? (Choose two answers.) -Discarding -Listening -Blocking -Forwarding -Learning Select 2 answers

-Forwarding -Learning Explanation: RSTP uses port state forwarding, learning, and discarding. Forwarding and learning perform the same functions as the port states used by traditional STP.

A router lists the following partial output from the show ip route command. Out which interface will the router route packets destined to IP address 10.1.15.122? -G0/0/0 -G0/2/0 -G0/3/0 -G0/1/0

-G0/3/0 Explanation: Destination address 10.1.15.122 matches all the routes listed except the host route to 10.1.15.100/32. In that case, the router will choose the matching route that has the longest prefix length, that is, the prefix-style mask with the highest number. In this case, that route lists subnet 10.1.15.96 and mask /27, which lists interface G0/3/0 as the outgoing interface.

The user at host A uses his browser to begin a session to Server 1. Which of the following would be true? -If the MAC address of Server 1 wasn't already known by Host A, Host A would use ARP to learn it. -Host A would be using a straight-through cable to connect to SW1. -The slowest link in the path is between R5 and the server. -Host A would need to learn the Layer 2 address of Server 1 before a session can be established.

-Host A would be using a straight-through cable to connect to SW1. Explanation: End devices like Host A use a straight-through cable to connect to a switch. (A router would also use a straight-through cable to connect to a switch). Every device, when forwarding traffic over an Ethernet-type connection will encapsulate and include in the frame the Layer 2 MAC address of the next device in the path. If the Layer 2 address isn't known, IPv4 protocol will use ARP (Address Resolution Protocol) to request and learn it. Host A doesn't need to learn any Layer 2 MAC addresses for devices in remote IP networks. Host A would need to know the MAC address of its default gateway (R1) and could use ARP to learn the local router's MAC address if not already in the ARP cache on Host A. With the labeling in the topology, all the Ethernet is running at Gigabit speed. The serial connection, which is a leased line, is usually much slower than the high-speed Ethernet. If there is a network slow point regarding bandwidth, it would be the serial link between R3 and R4.

Which type of error is purposefully triggered when using the traceroute command? -ICMP Redirect -ICMP Destination Unreachable -ICMP Information Reply -ICMP TTL Exceeded

-ICMP TTL Exceeded Explanation: The traceroute command (and its other sister alternatives) relies on the triggering of the ICMP TTL exceeded message (TTL= Time to Live). This message is used on each of the hops across the path to the destination; the reason is that the traceroute command purposefully sets the TTL (starting at 1 and then 2, 3, and so on) to force it to count down to 0 at each of the hops.

Which statement is true about the DR and BDR in OSPF? -If the DR fails, the BDR becomes the DR, and no new election will occur for the BDR. -If the DR fails, an election will occur for a new DR. -If the DR fails, the BDR becomes the DR, and when the DR is online again, it will resume as the DR. -If the DR fails, the BDR becomes the DR, and an election will occur for a new BDR.

-If the DR fails, the BDR becomes the DR, and an election will occur for a new BDR. Explanation: If the DR fails, the BDR becomes the DR, and an election will occur for a new BDR. If the DR comes back online, it will not resume as DR. There will not be another DR election because the BDR has become the DR upon failure of the original DR. The new election occurs for the BDR, not the DR.

When subnetting an IPv6 address block, an engineer shows a drawing that breaks the address structure into three pieces. Assuming that all subnets use the same prefix length, which of the following answers lists the name of the field on the far right side of the address? -Network -Interface ID -Subnet router anycast -Global routing prefix -Subnet

-Interface ID Explanation: Subnetting a global unicast address block, using a single prefix length for all subnets, breaks the addresses into three parts. The parts are the global routing prefix, subnet, and interface ID.

A network engineer configures the ip route 10.1.1.0 255.255.255.0 s0/0/0 command on a router and then issues a show ip route command from enable mode. No routes for subnet 10.1.1.0/24 appear in the output. Which of the following could be true? -Interface s0/0/0 is down -The ip route command has incorrect syntax and was rejected in config mode. -The router has no up/up interfaces in Class A network 10.0.0.0. -The ip route command is missing a next-hop router IP address.

-Interface s0/0/0 is down Explanation: The command uses correct syntax with the use of an outgoing interface. Those facts rule out two answers as incorrect. There is no requirement for a router to have any particular interface IP addresses in relation to the configuration of an ip route command, ruling out yet another answer. IOS performs several checks of the contents of a valid ip route command before adding the route to the routing table. It checks whether the outgoing interface is up/up (as noted in this question's correct answer), whether the next-hop address is reachable, and, if there is a competing route from another source, and whether the other route has a better administrative distance.

In the figure, the current STP state information is listed, with F for Forwarding and B for Blocking. SW1 is the current root. Assume that all STP parameters are using default values. Next, the network administrator configures a priority value of 61440 on SW1. Assuming that SW2 wins the new root election, which of the following statements is true about STP convergence? -Interfaces in a forwarding state before the change that need to stay in a forwarding state after SW2 becomes root will not transition to another STP state -The time spent in the listening state is defined by the Max Age timer. -The time spent in the listening state is defined by the Forward Delay timer. -SW2 interface fa0/3 will be in a learning state for 15 seconds. -SW2 interface fa0/3 will be in a listening state for 20 seconds. -SW3's fa0/2 interface will transition from a forwarding to a blocking state. Select 3 answers

-Interfaces in a forwarding state before the change that need to stay in a forwarding state after SW2 becomes root will not transition to another STP state -The time spent in the listening state is defined by the Forward Delay timer. -SW2 interface fa0/3 will be in a learning state for 15 seconds. Explanation: When the topology changes, if an interface that was blocking needs to move to a forwarding state, it must spend Forward Delay (default 15 seconds) time in both listening and learning states. If an interface was in a forwarding state, and it does not need to change to blocking, the interface simply stays in a forwarding state.

Which of the following statements describes part of the process of how a switch decides to forward a frame destined for a known unicast MAC address? -It forwards the frame out all interfaces in the same VLAN except for the incoming interface. -It compares the unicast source address to the bridging, or MAC address, table. -It compares the destination IP address to the destination MAC address. -It compares the frame's incoming interface to the source MAC entry in the MAC address table. -It compares the unicast destination address to the bridging, or MAC address, table.

-It compares the unicast destination address to the bridging, or MAC address, table. Explanation: A switch compares the destination MAC address to the MAC address table. If a matching entry is found, the switch forwards the frame out the appropriate interface. If no matching entry is found, the switch floods the frame.

In the figure, each link is labeled with a number. Which of the following statements are true about this network? -Link 13 uses a straight-through cable. -Link 10 uses a crossover cable. -Link 4 uses a crossover cable. -Link 3 uses a crossover cable.

-Link 13 uses a straight-through cable. -Link 3 uses a crossover cable. Explanation: Ethernet requires crossover cables between devices that use the same UTPpinouts - for instance, links between pairs of PCs, pairs of routers, and pairs of switches. (Hubs act like switches in terms of Ethernet cabling.) PCs, routers, and wireless APs use the same Ethernet pinouts, opposite from switches. Ethernet requires straight-through cables between devices that use opposite pinouts - for instance, for links between a PC and switch or between a router and switch.

PC1, PC2, and Router R1 all connect to the same VLAN and IPv6 subnet. PC1 wants to send its first IPv6 packet to PC2. What protocol or message will PC1 use to discover the MAC address to which PC1 should send the Ethernet frame that encapsulates this IPv6 packet? -NDP RS -SLAAC -NDP NS -ARP

-NDP NS Explanation: PC1 needs to discover PC2's MAC address. Unlike IPv4, IPv6 does not use ARP, instead using NDP. Specifically, PC1 uses the NDP Neighbor Solicitation (NS) message to request that PC2 send back an NDP Neighbor Advertisement (NA). SLAAC relates to address assignment, and not to discovering a neighbor's MAC address.

Refer to the diagram and exhibit; based on the information displayed, what is the cause of the connected interfaces having a "down" protocol state? -No configured interface clock rate -Mismatched IP subnets -No configured interface bandwidth -Disconnected cable

-No configured interface clock rate Explanation: Based on the information displayed, R1's S1/0 interface has the DCE cable connected to it, but the clock rate (number) command has not been configured on the interface.

Host A, in one Ethernet VLAN, needs to communicate using IPv6 to host B, which is in another Ethernet VLAN. Which answer best describes the protocol used by host A to learn the layer 2 address of Host B? -ARP -NDP -OSPFv3 -No protocol is used; A does not learn B's MAC address.

-No protocol is used; A does not learn B's MAC address. Explanation: Like IPv4 hosts, IPv6 hosts need to know the Layer 2 Ethernet address of another host in the same subnet, but not for hosts in another subnet. The question states that host B is in a different Ethernet VLAN, so it will be in a different IPv6 subnet than host A, with (at least) one router or layer 3 switch between host A's subnet and host B's subnet. As a result, host A never needs to learn host B's MAC address. For the incorrect answers... ARP is an IPv4 protocol to learn a local device's Layer 2 address and isn't used in IPv6. NDP (Neighbor Discovery Protocol) is used to learn Layer 2 Ethernet addresses when needed, but only functions within the same VLAN. OSPFv3 is a routing protocol used by routers, so it does learn information about other IPv6 subnets - routes to those subnets - but it isn't a protocol to learn the Layer 2 address of a neighbor.

Which of the following routing protocols is considered to use link-state logic? -RIPv1 -EIGRP -RIPv2 -OSPF

-OSPF Explanation: Both versions of RIP use distance vector logic, and EIGRP uses a different kind of logic, characterized either as advanced distance vector or a balanced hybrid.

The figure shows a network in which IPv4 will be implemented on all interfaces. Static IPv4 routes will be used, but no routing protocols. The exhibit includes the output of the show ip interfaces command to list R1's IPv4 addresses, along with the IPv4 routes the engineer intends to add to the configuration on R1. You may assume that all the other routers will be configured with correct IPv4 static routes (not shown for this question). Once the engineer adds the ip route commands shown in the exhibit to router R1's configuration, where will R1 forward packets to the destinations listed? Exhibit: { R1# show ip interface brief Interface IP-Address OK? Method Status Protocol GigabitEthernet0/0 10.255.1.69 YES NVRAM administratively down down GigabitEthernet0/1 172.16.12.1 YES NVRAM up up GigabitEthernet0/2 172.16.13.1 YES manual up up GigabitEthernet0/3 172.16.14.1 YES manual down down GigabitEthernet0/4 172.16.1.1 YES manual up up ! Commands to add per the question: ip route 172.16.5.1 255.255.255.255 172.16.14.4 160 ip route 172.16.6.2 255.255.255.255 172.16.13.3 150 ip route 172.16.5.0 255.255.255.0 172.16.12.2 ip route 172.16.6.0 255.255.255.128 172.16.12.2 130 } -Packets sent to server S2 will be discarded. -Packets sent to server S1 will flow from R1 to R2 next. -Packets sent to server S2 will flow from R1 to R2 next. -Packets sent to server S1 will be discarded. -Packets sent to server S2 will flow from R1 to R3 next. -Packets sent to server S1 will flow from R1 to R4 next. Select 2 answers

-Packets sent to server S1 will flow from R1 to R2 next. -Packets sent to server S2 will flow from R1 to R3 next. Explanation: The first key to answering this question is to notice that R1's G0/3 interface is not in an up/up state. Per the figure, R1's G0/3 connects to router R4, with IP address 172.16.14.4. So, of the four ip route commands, the command with 172.16.14.4 as the next-hop address will be added to the configuration but will not be added to R1's IP routing table currently. That fact rules out one answer (that packets sent to server S1 are sent to R4 next) as a correct answer. Next, examine the other three ip route commands closely. All reference either 172.16.12.2 (R2) or 172.16.13.3 (R3) as next hop. Per the show ip interface brief command and the figure, R1's interfaces connected to those neighboring routers are in an up/up state. Next, note that while those commands list different administrative distance values, none of the ip route commands list the exact same prefix and mask. IOS uses the administrative distance only to distinguish between routes when the destination and mask exactly match. As a result, the various administrative distance values in this question have no impact on which routes R1 adds to its routing table. Given those facts, for packets sent to server S2 (172.16.6.2), the packet matches two routes: the host route to specifically 172.16.6.2/32, and the route to subnet 172.16.6.0/25. R1 will use the more specific route—that is, the route with the longer prefix mask, which uses R3 (172.16.13.3) as the next-hop address. The following output shows the static routes added to R1's IPv4 routing table per the scenario in this lab: R1# show ip route static ! Legend omitted for brevity 172.16.0.0/16 is variably subnetted, 9 subnets, 3 masks S 172.16.5.0/24 [1/0] via 172.16.12.2 S 172.16.6.0/25 [130/0] via 172.16.12.2 S 172.16.6.2/32 [150/0] via 172.16.13.3

The goal in a lab network is to configure the devices so that the PCs can ping each other. The exhibit shows the configuration planned for the routers. Which answers identify the reason why the pings fail? Exhibit { Host A IP address: 192.168.100.100 Subnet Mask: 255.255.255.0 Gateway: 192.168.100.1 ----- Host B IP address: 192.168.200.100 Subnet Mask: 255.255.255.0 Gateway: 192.168.200.1 ----- R1 ! hostname R1 ! interface FastEthernet0/0 ip address 10.10.10.1 255.255.255.252 ip ospf 20 area 0 ! interface FastEthernet0/1 no ip address shutdown ! interface FastEthernet1/0 ip address 192.168.100.1 255.255.255.0 ip ospf 20 area 0 ! interface FastEthernet1/1 no ip address shutdown duplex auto speed auto ! router ospf 20 passive-interface FastEthernet1/0 router-id 1.1.1.1 ----- R2 hostname R2 ! interface FastEthernet0/0 ip address 10.10.10.2 255.255.255.252 ip ospf 10 area 0 ! interface FastEthernet0/1 no ip address shutdown ! interface FastEthernet1/0 ip address 192.168.200.1 255.255.255.0 ! interface FastEthernet1/1 no ip address shutdown ! router ospf 10 passive-interface FastEthernet1/0 router-id 2.2.2.2 } -There is a process ID mismatch between routers. -R2 fails to enable OSPF on all interfaces. -The passive interface is incorrectly configured on R1. -There is an overlapping router ID.

-R2 fails to enable OSPF on all interfaces. Explanation: The configuration mistake exists on router R2. R2 should enable OSPF on both interfaces shown in the figure (F0/0 and F1/0), but the configuration does not include the command to enable OSPF on the F1/0 interface. As a result, R2 does not advertise about the subnet connected to its F1/0 interface, so that R1 does not learn a route to that subnet. Of the incorrect answers, one answer suggests that the router IDs overlap. However, the configurations show both routers with explicitly-configured different RIDs (1.1.1.1 and 2.2.2.2). Another answer mentions that they use different process IDs in the router ospf commands. However, neighboring routers can use different process ID values, so that is not a mistake. Finally, one incorrect answer mentions the passive-interface setting on router R1. R1 makes it F1/0 interface passive for OSPF, but no other routers exist on that interface, so that is the exact condition in which to use the passive-interface feature.

Refer to the provided topology diagram. Network 1 uses subnet 10.0.35.0/27Network 2 uses subnet 172.16.192.0/26Network 3 uses subnet 192.168.255.0/24 Which of the following are true? -R1's G1/0 interface could be any address in the range of 10.0.35.1-10.0.35.62. -The broadcast address of network 2 is 172.16.192.255. -R3's S3/0 could use the address of 192.168.255.3/24. -Host A's address could be 10.0.35.31/27. -The addresses used for networks 1, 2, and 3 are all within the private IP address ranges.

-R3's S3/0 could use the address of 192.168.255.3/24. -The addresses used for networks 1, 2, and 3 are all within the private IP address ranges. Explanation: The private IPv4 address range includes 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16, and networks 1, 2, and 3 are each within one of those ranges. Network 3's range is 192.168.255.1-255, and the address of 192.168.255.3 is within that valid host range. Network 1 is subnet 10.0.35.0/27, with a valid host range of 10.0.35.1-30 (not 10.0.35.1-10.0.35.62). Host A's proposed address of 10.0.35.31/27 is the broadcast address for the subnet and couldn't be used as a host's IP address on that subnet. The broadcast address for network 2 is 172.16.192.63 (not 172.16.192.255).

Which of the following interior routing protocols support VLSM? (Choose three answers.) -RIPv1 -RIPv2 -EIGRP -OSPF Select 3 answers

-RIPv2 -EIGRP -OSPF Explanation: Of the listed routing protocols, only the old RIP Version 1 (RIP-1) protocol does not support variable-length subnet masks (VLSM).

Which layer of the TCP/IP Model defines end-to-end forwarding of packets? -The Network layer -The Application layer -The Link layer -The Transport layer

-The Network layer Explanation: The TCP/IP Network layer defines the end-to-end routing of data. Also, the term packet (as mentioned in the question) defines the data that the network layer forwards from sending host to destination host. For the incorrect answers: The TCP/IP Application layer provides application software with an interface to the network in ways that simplify the interface so that the application can ask the network to deliver data to some destination address. The TCP/IP Transport layer deals with error recovery, segmentation of large application data blocks for transport, and the reassembly of segmented application data. The TCP/IP data link layer defines how to deliver data over a particular instance of a particular type of data link, for instance, over a single Ethernet LAN, serial WAN, or Ethernet WAN link. However, it does not define end-to-end routing of data.

Imagine a network with two routers that are connected with a point-to-point HDLC serial link. Each router has an Ethernet, with PC1 sharing the Ethernet with Router1 and PC2 sharing the Ethernet with Router2. When PC1 sends data to PC2, which of the following is true? -Router1 removes the Ethernet, IP, and TCP headers and rebuilds the appropriate headers before forwarding the packet to Router2. -Router1 strips the Ethernet header and trailer off the frame received from PC1, never to be used again. -Router1 encapsulates the Ethernet frame inside an HDLC header and sends the frame to Router2, which extracts the Ethernet frame for forwarding to PC2. -Router1 strips the Ethernet header and trailer off the frame received from PC1, which is exactly re-created by Router2 before forwarding data to PC2.

-Router1 strips the Ethernet header and trailer off the frame received from PC1, never to be used again. Explanation: PC1 will send an Ethernet frame to Router 1, with PC1's MAC address as the source address and Router 1's MAC address as the destination address. Router 1 will remove the encapsulated IP packet from that Ethernet frame, discarding the frame header and trailer. Router 1 will forward the IP packet by first encapsulating it inside an HDLC frame, but Router 1 will not encapsulate the Ethernet frame in the HDLC frame but rather the IP packet. Router 2 will de-encapsulate the IP packet from the HDLC frame and forward it onto the Ethernet LAN, adding a new Ethernet header and trailer, but this header will differ. It will list Router 2's MAC address as the source address and PC2's MAC address as the destination address.

Which of the following is a difference between Telnet and SSH as supported by a Cisco switch? -Telnet encrypts only password exchanges; SSH encrypts all data exchanges. -SSH encrypts all data exchange, including login passwords; Telnet encrypts nothing. -Telnet is used from Microsoft operating systems, and SSH is used from UNIX and Linux operating systems. -SSH encrypts the passwords used at login, but not other traffic; Telnet encrypts nothing.

-SSH encrypts all data exchange, including login passwords; Telnet encrypts nothing. Explanation: SSH provides a secure remote login option, encrypting all data flows, including password exchanges. Telnet sends all data (including passwords) as clear text.

Which spanning-tree modes are IEEE standards? -STP -RSTP -PVST+ -RPVST+ -MSTP Select 3 answers

-STP -RSTP -MSTP Explanation: Cisco created its own proprietary spanning-tree features; they are Per VLAN Spanning Tree Plus (PVST+) and Rapid Per-VLAN Spanning Tree Plus (RPVST+). The other options are IEEE standards.

The figure shows a LAN with three switches, a router using 802.1Q trunking, and VLANs 11 and 13. Subnet 10.1.1.0/24 is on VLAN 11, and subnet 10.1.3.0/24 is on VLAN 13. The STP topology has converged for each VLAN, with SW3 blocking on fa0/1 for VLAN 11, and SW2 blocking on fa0/1 for VLAN 13. Assume that the PCs and router have complete and full information in their ARP tables and that all three switches have current and valid MAC address table entries for the MAC addresses of the PCs and the router. Under those conditions, which of the following statements best describes the MAC address tables used in each VLAN? -When PC1 pings PC3, the ICMP Echo request never passes through SW2. -When PC1 pings its default gateway, the ICMP Echo request takes a different path than the ICMP Echo reply. -SW1's MAC table for VLAN 11 lists PC2's MAC with interface fa0/2. -SW1's MAC table for VLAN 11 lists R1's MAC with interface fa0/2.

-SW1's MAC table for VLAN 11 lists PC2's MAC with interface fa0/2. -SW1's MAC table for VLAN 11 lists R1's MAC with interface fa0/2. Explanation: The key point for this question is remembering that MAC address tables are built based on the source MAC address of a frame and the interface in which the frame was received. The switches keep a separate MAC address table for each VLAN. SW2 will, of course, have an entry for PC2's MAC referencing SW2's fa0/4 interface. To know the contents of SW1's VLAN 11 MAC address table entry for PC2, consider the interfaces in which SW1 could have received a frame from PC1. Because SW3's fa0/1 interface is blocking in VLAN 11, a frame that PC2 sends will never arrive in SW1's fa0/1 interface, but it will arrive in SW1's fa0/2 interface. That is why SW1 has added a MAC table entry, in VLAN 11, for PC2's MAC, off interface fa0/2. Because R1 is trunking and creating frames with its own MAC address as the source MAC of the frames, R1's MAC address shows up in both the VLAN 11 and VLAN 13 MAC address tables. SW2 always adds an entry for R1's MAC, interface fa0/11. Next, consider in which interface SW1 will receive frames sent by R1, in VLAN 11. Because SW3 blocks in VLAN 11, the frames that R1 sends, in VLAN 11 at least, can only get to SW1 in SW1's fa0/2 interface. Therefore, SW1 will have added an entry into its VLAN 11 MAC table, for R1's MAC, off SW1's interface fa0/2. When PC1 pings PC3, the ICMP Echo request must be routed to another subnet. A frame that is holding the request first goes from PC1 to the router inside VLAN 11, and then back out of the router and on to PC3 inside VLAN 13. Any frames that are sent to the router have to pass through SW2. The answer with PC1 pinging its default gateway means that PC1 will send a frame to R1's MAC, in VLAN 11, and that R1 will send a frame to PC1's MAC, also in VLAN 11. Because SW3 is blocking on its fa0/1 interface in VLAN 11, the only possible path through the switches for the PC1-to-R1 frame is from PC1, to SW1, to SW2, and then to R1. Likewise, the only possible return path, because of the STP topology, is the reverse path. Note that the exam engine links to a PDF of chapter 7, but chapter 3 also covers several topics helpful in answering this question. The switches keep a separate MAC address table for each VLAN. SW2 will, of course, have an entry for PC2's MAC referencing SW2's fa0/4 interface. To know the contents of SW1's VLAN 11 MAC address table entry for PC2, consider the interfaces in which SW1 could have received a frame from PC1. Because SW3's fa0/1 interface is blocking in VLAN 11, a frame that PC2 sends will never arrive in SW1's fa0/1 interface, but it will arrive in SW1's fa0/2 interface. That is why SW1 has added a MAC table entry, in VLAN 11, for PC2's MAC, off interface fa0/2. Because R1 is trunking and creating frames with its own MAC address as the source MAC of the frames, R1's MAC address shows up in both the VLAN 11 and VLAN 13 MAC address tables. SW2 always adds an entry for R1's MAC, interface fa0/11. Next, consider in which interface SW1 will receive frames sent by R1, in VLAN 11. Because SW3 blocks in VLAN 11, the frames that R1 sends, in VLAN 11 at least, can only get to SW1 in SW1's fa0/2 interface. Therefore, SW1 will have added an entry into its VLAN 11 MAC table, for R1's MAC, off SW1's interface fa0/2. When PC1 pings PC3, the ICMP Echo request must be routed to another subnet. A frame that is holding the request first goes from PC1 to the router inside VLAN 11, and then back out of the router and on to PC3 inside VLAN 13. Any frames that are sent to the router have to pass through SW2. The answer with PC1 pinging its default gateway means that PC1 will send a frame to R1's MAC, in VLAN 11, and that R1 will send a frame to PC1's MAC, also in VLAN 11. Because SW3 is blocking on its fa0/1 interface in VLAN 11, the only possible path through the switches for the PC1-to-R1 frame is from PC1, to SW1, to SW2, and then to R1. Likewise, the only possible return path, because of the STP topology, is the reverse path. Note that the exam engine links to a PDF of chapter 7, but chapter 3 also covers several topics helpful in answering this question.

Review the topology. All subnets exist in OSPF area 0. Which command, if issued on R3, would show all the LSAs known by R3? -Show ip ospf interface -Show ip ospf database -Show ip ospf neighbors -Show running-config -Show ip route ospf

-Show ip ospf database Explanation: The command show ip ospf database will show the LSAs known by that router. The show running-config, show ip ospf interface, show ip ospf neighbors, and show ip route ospf commands are all valid commands that can assist in the verification and troubleshooting of OSPF, but they do not show the LSAs known to the router in OSPF.

Which of the following is not a solution to the IPv4 address shortage problem? -Subnet broadcast addresses -Network Address Translation (NAT) -The development of IPv6 -More careful and reduced address assignments to businesses

-Subnet broadcast addresses Explanation: There were three main solutions to the IPv4 address shortage worked on intensely in the 1990s. These were the development of what we now term IPv6, the Network Address Translation process with private IP addresses, and the careful assignment of smaller portions of the public address space to businesses. Subnet broadcast addresses happen to be a useful feature of IP, but has nothing to do with conserving the IPv4 address space.

Which type of encryption should be avoided when encrypting data in a wireless environment? -CCMP -TKIP -GCMP -AES

-TKIP Explanation: TKIP happens to be an interim solution to overcome some security shortcomings with early 802.11 security protocols, specifically with WEP. With the passage of time and development of newer standards, TKIP should no longer be used and is in fact deprecated (removed) from the 802.11 standard. The other answers describe different features of current 802.11 security features. For reference: - TKIP: Temporary Key Integrity Protocol. - CCMP: Counter CBC-MAC Protocol. - GCMP: Galois Counter Mode Protocol. - AES: Advanced Encryption Standard.

Which of the following would be in a forwarding state in RSTP? -Alternate ports -The root port on a nonroot switch -All the root ports on the root switch -Designated ports

-The root port on a nonroot switch -Designated ports Explanation: As for the correct answers, root ports (which exist only on nonroot switches) are in a forwarding state. Designated ports are also in a forwarding state. Additionally, an edge port with RSTP connects to a single non-switch device, meaning it will be the designated port, and therefore reach a forwarding state. As for the incorrect answers, the RSTP backup and alternate port roles exist for a port to take over for some other designated port or root port, respectively. However, while in the backup or alternate role, the port is in a discarding state. Also, for the answer that mentions "root ports on the root switch", note that the root switch has no root port.

Using the provided network topology, you have been asked to configure the following IPv4 subnets: Network 1, use subnet 172.16.8.0/21 Network 2, use subnet 172.16.16.0/21 Network 3, use subnet 172.16.24.0/21 Network 4, use subnet 172.16.32.0/21 Based on this information, which of the following are true? -Network 3's broadcast address is 172.16.24.255. -The address of 172.16.9.255/21 could be used on R1s G1/0 interface. -This base network is a Class B network. -Each of these four subnets can support a maximum of 2048 host addresses each. -The subnet broadcast address for network 4 is 172.16.39.255. Select 3 answers

-The address of 172.16.9.255/21 could be used on R1s G1/0 interface. -This base network is a Class B network. -The address of 172.16.9.255/21 could be used on R1s G1/0 interface. -This base network is a Class B network. Explanation: Any IPv4 address beginning with 172 is a Class B address, with a default mask of /16. The broadcast address for 172.16.32.0/21 is 172.16.39.255. Network 1's range is 172.16.8.1-172.16.15.254, and the address that R1 could use on its G1/0 interface of 172.16.9.255 is within that valid host range. With 11 host bits available, each subnet could support 2046 hosts on each /21 network (not 2048). Network 3's range is 172.16.24.1-172.16.31.254, and the broadcast address would be 172.16.31.255 (not 172.16.24.255).

In the figure, CAT5 cabling with RJ-45 connectors is used. Which of the following statements are true about the wires inside the cable and the RJ-45 pins to which they are connected? -The cable from PC1 to SW1 connects pin 6 on one end to pin 6 on the other. -The cable from SW1 to SW2 connects pin 6 on one end to pin 3 on the other. -The cable from PC1 to SW1 connects pin 2 on one end to pin 7 on the other. -The cable from SW1 to SW2 connects pin 1 on one end to pin 8 on the other.

-The cable from PC1 to SW1 connects pin 6 on one end to pin 6 on the other. Straight-through cables are used on the links between a switch and a PC, and between a switch and a router. The link between switches uses a crossover cable, which connects pins 1 and 3, 2 and 6, 3 and 1, and 6 and 2.

In the figure, all devices are statically configured with the IP addresses, masks, and default gateway information. Assume that all switches have learned the MAC addresses of all devices in the figure. PC1 pings PC4, and PC1 receives replies, confirming that the ping worked. Which of the following are true about the frames sent in this network, and their encapsulated packets? When considering a frame, consider the header of the frame, and any encapsulated packet as well. -The frame that contains the ICMP Echo request, sent by PC1, has a destination MAC address of R1's fa0/0 interface's MAC. -The frame that contains the ICMP Echo request, sent by PC1, has a destination MAC address of PC4's MAC. -The frame that contains the ICMP Echo request, sent by PC1, has a destination IP address of 10.1.1.254. -The frame that contains the ICMP Echo request, sent by PC1, has a destination IP address of 10.1.2.4. -The frame that contains the ICMP Echo reply, sent by PC4, has a destination MAC address of R1's fa0/0 interface's MAC. -The frame that contains the ICMP Echo reply, sent by PC4, has a destination MAC address of PC1's MAC.

-The frame that contains the ICMP Echo request, sent by PC1, has a destination MAC address of R1's fa0/0 interface's MAC. -The frame that contains the ICMP Echo request, sent by PC1, has a destination IP address of 10.1.2.4. Explanation: In this example, PC1 and PC4 reside in different subnets, with one router between them. As a result, the router de-encapsulates the IP packet (holding the ICMP message) from the Ethernet frame, discarding the old Ethernet header and trailer - and then adding a new Ethernet header and trailer. Each frame uses a destination MAC address of a device on the same LAN or broadcast domain. Considering an ICMP Echo message sent by PC1 to PC4, the frame encapsulating the ICMP message uses: The IP header shows PC1's IPv4 address as the source and PC4's IPv4 address as the destination. The Ethernet header of the frame as sent by PC1 includes a source MAC of PC1's MAC and a destination MAC of R1-fa0/0's MAC. The Ethernet header of the frame after the router routes the packet (including de-encapsulation and re-encapsulation) shows a source MAC of R1-Fa0/1's MAC and PC4's MAC address as the destination. In the reverse direction, with PC4 sending an ICMP Echo Reply: The IP header shows PC4's IPv4 address as the source and PC1's IPv4 address as the destination. The Ethernet header of the frame sent by PC4 shows PC4's MAC address as the source and R1-Fa0/1's MAC as the destination. The Ethernet header of the frame after the router routes the packet (including de-encapsulation and re-encapsulation) shows the R1-Fa0/0's MAC as the source and PC1's MAC address as the destination. If you apply all these facts to the various answers, you can rule in and rule out each correct and incorrect answer, respectively.

A network engineer spends time thinking about the entire Class B network 172.16.0.0 and how to subnet that network. He then chooses how to subnet this Class B network and creates an addressing and subnetting plan, on paper, showing his choices. If you compare his thoughts about this network before subnetting the network to his thoughts about this network after mentally subnetting the network, which of the following occurred to the parts of the structure of addresses in this network? -The network part got smaller. -The host part was removed. -The subnet part got smaller. -The host part got smaller. -The network part was removed.

-The host part got smaller. Explanation: An unsubnetted Class A, B, or C network has two parts: the network and host parts. To perform subnetting, the engineer creates a new subnet part by borrowing host bits, shrinking the number of host bits. The subnet part of the address structure exists only after the engineer chooses a nondefault mask. The network part remains a constant size.

Which of the following statements are true regarding the binary subnet ID, subnet broadcast address, and host IP address values in any single subnet? (Choose two answers.) -The host part of the broadcast address is all binary 0s. -The host part of the subnet ID is all binary 0s. -The host part of a usable IP address can have all binary 1s. -The host part of any usable IP address must not be all binary 0s. Select 2 answers

-The host part of the subnet ID is all binary 0s. -The host part of any usable IP address must not be all binary 0s. Explanation: In any subnet, the subnet ID is the smallest number in the range, the subnet broadcast address is the largest number, and the usable IP addresses sit between them. All numbers in a subnet have identical binary values in the prefix part (classless view) and network + subnet part (classful view). To be the lowest number, the subnet ID must have the lowest possible binary value (all 0s) in the host part. To be the largest number, the broadcast address must have the highest possible binary value (all binary 1s) in the host part. The usable addresses do not include the subnet ID and subnet broadcast address, so the addresses in the range of usable IP addresses never have a value of all 0s or 1s in their host parts.

Refer to the diagram and exhibit; an engineer is checking the work of a co-worker who is responsible for developing the ROAS configuration of R1. Which options are true of the potential configuration of R1? -It will work fine, as expected. -The VLAN assignment commands are all using the wrong syntax. -The physical interface has a command that is invalid. -The interfaces handling the VLAN 30 and 40 traffic have their assignment commands reversed. -The mismatch of VLAN IDs and subinterface numbers will prevent the trunk from working. -The interfaces handling the VLAN 20 and 40 traffic have their assignment commands reversed. Select 2 answers

-The physical interface has a command that is invalid. -The interfaces handling the VLAN 30 and 40 traffic have their assignment commands reversed. Explanation: There are a few problems that exist in this potential configuration. -First, the encapsulation dot1q command is not allowed under the physical interface, but it is shown in the configuration. That command is used only under ROAS subinterfaces. -Second, the native VLAN should be configured to be processed by one special subinterface or by the physical interface, but not both. To process the native VLAN with the physical interface, you would simply give the physical interface an IP address, as is shown here. However, the encapsulation dot1q 30 native subcommnand tells the router to process the native VLAN's traffic on the matching subinterface. A correct configuration should do one or the other, but not both. Finally, the VLAN assignment commands (encapsulation dot1q) that are configured on subinterfaces Gi0/0.200 and Gi0/0.300 are reversed; this would cause traffic to be handled by the wrong subinterfaces in comparison to the figure. It is also important to note that the subinterface numbers that are used do not affect VLAN assignments; they are separate. While it is considered best practice to use numbers that are easy to reference, it is not required.

The command output shows two routes from the longer output of the show ipv6 route command. Which answers are true about the output? -The route to 2001:DB8:2:2::/64 is added because of an IPv6 routing protocol. -The route to ::/0 is added because of an ipv6 address interface subcommand. -The route to ::/0 is added because of an ipv6 route global command. -The administrative distance of the route to 2001:DB8:2:2::/64 is 1. Select 2 answers

-The route to ::/0 is added because of an ipv6 route global command. -The administrative distance of the route to 2001:DB8:2:2::/64 is 1. Explanation: The output shows two static routes, as noted with the "S" code on the far left. Both were added to the IPv6 routing table because of ipv6 route commands. Both have an administrative distance of 1, which is listed as the first number in brackets. For the two incorrect answers, note that the ipv6 address interface subcommand does cause IOS to add connected IPv6 routes to the routing table, and the phrase "directly connected" with one route might make you think this is a connected route. However, the "S" in the far left identifies the source of the route. Likewise, the answer that mentions an IPv6 routing protocol is incorrect because both routes have a code of S, meaning static.

After power on, a frame arrives at a switch. The switch had not yet learned the source MAC address of that frame. Which actions must the switch take in this case? -The switch adds the source MAC address to its MAC table. -The switch adds the source and destination MAC address to the MAC address table. -The switch adds the destination MAC address to the MAC address table. -The switch checks the frame for loops.

-The switch adds the source MAC address to its MAC table. Explanation: This scenario focuses on switch learning. First, for switch learning, the switch's MAC address table may have some MAC addresses in it, but it does not contain the source MAC address of the frame. Switch learning means that the switch learns the source MAC address of the frame (identifying the one correct answer). Switches do not learn based on the destination MAC address of the frame (ruling out two answers). One incorrect answer mentions a frame loop. The frame does not contain any fields that allow a check to discover if the frame has been looping through the switch.

This output comes from a network analysis tool. It lists a group of lines for each header in a PDU, with the frame (data link) header at the top, then the next header (typically the IP header), and so on. The first line in each section has a gray highlight, with the indented lines below each heading line listing details about the fields inside the respective header. You will need to remember some parts of the various headers, and compare those concepts to this output, to answer this question. The switch had just been powered on, and the first frame sent was the one shown in the packet capture shown here. Immediately following this frame entering the switch, which of the following are true? -The switch dynamically knows which port PC 1 is connected to. -This frame of data was forwarded by the switch only to PC 2. -This frame is a broadcast and was forwarded to PC 2, PC 3 and PC 4 by the switch. -PC 3 and PC 4, once they see the frame is not relevant to them, will discard the frame.

-The switch dynamically knows which port PC 1 is connected to. -This frame of data was forwarded by the switch only to PC 2. Explanation: Looking at the Layer 2 Ethernet source and destination of the frame in the output, we can see that the source is 00.00.11.11.11.11 and the destination of the frame is ff.ff.ff.ff.ff.ff, which is a Layer 2 broadcast. Switches forward Layer 2 broadcasts to all other ports in the same VLAN. In this case, the only other port in VLAN 2 is port Fa0/2, so PC 2 will see the frame. Switches do not forward frames back to the port the frame came in on. The moment PC 1 sent the frame, the switch dynamically added the MAC address information to the MAC address table. Switches do not forward broadcasts outside of the VLAN on which the broadcast came in. PC 3 and PC 4 are in VLAN 3, and the broadcast came in on a switch port assigned to VLAN 2. As a result, PC 3 and PC 4 would never even see the frame, because the switch would not forward it to them.

Which command administratively disables trunking on a 2960XR switch interface, such that the switch cannot use a trunking protocol on the interface? Assume that all commands shown in the answers are used in interface configuration mode. -The switchport mode access command -The no switchport mode trunk command -The no switchport trunk command -The switchport trunk disable command -The switchport access vlan x command -The switchport mode off command

-The switchport mode access command Explanation: The switchport mode access command tells the switch not to attempt to dynamically form a trunk and not to use trunking on the interface. The no switchport mode trunk command tells the switch to revert to the default setting for trunk negotiation. The default on most Cisco Catalyst switches, including those in the various 2960 series switches, is dynamic auto, which tells the switch to react to any received negotiation messages. One incorrect answer mentions the no switchport mode trunk command, which tells the switch to revert to the default setting for trunk negotiation. The default on most Cisco access switches is switchport mode dynamic auto, which tells the switch to react to any received negotiation messages. So the switch port would negotiate trunking if the neighboring switch requested it. Another incorrect answer lists the switchport access vlan x command. This command defines the VLAN to statically assign to the port if it acts as an access port, but the command does not prevent the switch from attempting to negotiate trunking on the port. The remaining incorrect answers show commands that do not exist in Cisco switches.

The exhibit shows the output of a couple of show commands. Which of the following statements is true about the trunk shown in the exhibit? -The switchport mode command, on the switch on the other end of port fa0/1, must have a setting of either dynamic desirable, dynamic auto, or trunk. -The switchport mode command, on the switch on the other end of port fa0/1, must have a setting of either dynamic desirable or trunk. -VLAN 3 traffic is not allowed to cross the fa0/1 trunk. -VLAN 3 traffic does not have an 802.1Q header as it crosses the fa0/1 trunk. -Traffic from VLANs 900 and 901 is not allowed to cross the fa0/1 trunk. -The switchport mode command, on the switch on the other end of port fa0/1, must have a setting of dynamic desirable. Select 3 answers

-The switchport mode command, on the switch on the other end of port fa0/1, must have a setting of either dynamic desirable or trunk. -VLAN 3 traffic does not have an 802.1Q header as it crosses the fa0/1 trunk. -Traffic from VLANs 900 and 901 is not allowed to cross the fa0/1 trunk.

Interface fa0/1 begins with all default interface configuration. Which answers list a single interface subcommand that would cause the switch to no longer attempt to dynamically form a trunk with a neighboring switch? -The switchport nonegotiate subcommand. -The vlan 10 access subcommand. -The switchport mode access subcommand. -The switchport mode trunk subcommand. Select 2 answers

-The switchport nonegotiate subcommand. -The switchport mode access subcommand. Explanation: A switch port stops attempting to use Dynamic Trunking Protocol (DTP) to negotiate trunking in two cases (matching the two correct answers.) The configuration can disable DTP using the switchport nonegotiate subcommand. Additionally, setting the administrative trunking mode to access, using the switchport mode access subcommand, also disables DTP. One incorrect answer lists the command switchport mode trunk. This command statically enables trunking, but it leaves DTP enabled to allow negotiation with the neighboring switch. One incorrect answer lists an invalid command: vlan 10 access.

What statement is true about the command ipv6 unicast-routing? -This command is required for the operation of IPv6 routing on the device. -This command is required for the dynamic assignment of IPv6 addresses to interfaces. -This command has been deprecated and is no longer recommended. -This command is required for the assignment of IPv6 addresses to interfaces.

-This command is required for the operation of IPv6 routing on the device. Explanation: This important command has not been deprecated and is used to configure the router to actually route IPv6 packets. The command is not required for the configuration of static or dynamic IPv6 addresses.

The WPA wireless security suites are defined by which of the following entities? -Wi-Fi Alliance -Cisco -FCC -IEEE

-Wi-Fi Alliance Explanation: The Wi-Fi Alliance defines all versions of the Wi-Fi Protected Access (WPA) security suite. The IEEE is not a correct answer because it defines and maintains many networking standards, including 802.11 and 802.1x, which are used in wireless networking. The FCC is not a correct answer because it is the governing body in the United States that regulates RF frequencies, channels, and transmission power. Cisco is not a correct answer because it designs and manufactures wireless networking products that must adhere to the WPA standards, but not define them.

Refer to the diagram. An engineer issued the ping 192.168.3.100 command from R1, and the ping was successful. Are there any routes that would not be verified as working by that successful ping? -No, all routes in the network have been verified. -Yes, R2's route to the subnet off R1's G0/1 interface. -Yes, the route between PC1 and its default gateway (R1) -Yes, the route between PC2 and its default gateway (R2) Select 2 answers

-Yes, R2's route to the subnet off R1's G0/1 interface. -Yes, the route between PC1 and its default gateway (R1) Explanation: This question highlights a common mistake: a ping from R1 to PC2 verifies the connectivity between R1's Gi0/2 interface and the rest of the network to its right; however, it does not verify connectivity between PC1 to R1's Gi0/1 subnet. The reason in this case is that a simple ping from R1 to PC2 will use the IP address of R1's Gi0/2 interface. A way to verify the subnet to the left of R1 and for all of R1's interfaces would be to use the extended ping command and use a source IP address from R1's Gi0/1 interface. Note that a standard ping from R1 also does not test the users' default gateway settings. For instance, in this case, PC1 did not exercise its default gateway setting for the ping test used on R1. However, because PC2 had to send a message, PC2's default gateway setting was tested.

What command completely replaces the contents of one of the configuration files in a switch? -copy tftp system:running-config -copy tftp running-config -copy running-config startup-config -copy startup-config running-config

-copy running-config startup-config Explanation: Any command that copies from any source configuration file, into the startup-config file in NVRAM, replaces the startup-config file. Also, any command that copies a config file to an external server also replaces the file on that server. However, any command that copies into the running-config file merges the configuration rather than replacing the running-config file. Of the listed answers, only the correct answer lists the startup-config file as the destination of the copy command. The three incorrect answers list the running-config file as the destination file.

What command copies the configuration from RAM into NVRAM? -copy startup-config running-config -copy tftp running-config -copy running-config tftp -copy start-up-config running-config -copy running-config startup-config -copy running-config start-up-config

-copy running-config startup-config Explanation: The startup-config file is in NVRAM, and the running-config file is in RAM.

Which command will generate the SSH encryption keys? -crypto key generate rsa -crypto key modulus ssh -crypto key generate ssh -crypto key modulus rsa

-crypto key generate rsa Explanation: The crypto key generate rsa command will generate the SSH encryption keys. The incorrect answers are not commands supported on Cisco routers and switches.

Refer to the diagram. Which static route statements on R1 would be configured to ensure that: - all normal device traffic going to the 30.30.30.0 network would be routed via the primary path, and - all traffic going to ServerA would be routed via the high-priority path? -ip route 30.30.30.0 255.255.255.0 20.20.20.2 -ip route 30.30.30.100 0.0.0.0 10.10.10.2 -ip route 30.30.30.100 255.255.255.255 10.10.10.2 -ip route 30.30.30.0 0.0.0.255 20.20.20.2 Select 2 answers

-ip route 30.30.30.0 255.255.255.0 20.20.20.2 -ip route 30.30.30.100 255.255.255.255 10.10.10.2 Explanation: Two different static route statements are needed to meet the requirements: one routes all normal traffic, and the other is specific to the traffic destined for ServerA. The first correct statement is ip route 30.30.30.0 255.255.255.0 20.20.20.2. The 255.255.255.0 mask matches all traffic destined for addresses that begin with exactly 30.30.30, while the fourth octet can be any valid number. The second correct statement is a host route; it is ip route 30.30.30.100 255.255.255.255 10.10.10.2. The 255.255.255.255 mask matches all traffic destined for only the 30.30.30.100 address. The two incorrect statements both use invalid masks.

You are in the process of troubleshooting a network problem on a Cisco device, but you are having a problem getting the right commands entered on the device to fix it. The reason is that every time you attempt to configure the commands, the console generates another message, your command gets split, and you lose your place in the command. What command could you configure on the device to have it automatically place the commands that are entered onto a fresh line and redrawn up to the point where the command entry was interrupted? -logging console redraw -logging synchronous -logging console brief -logging regenerate

-logging synchronous Explanation: The logging synchronous command alters the way that console messages are printed onto a screen. The first thing it will do is print only console messages on new lines, but this would interrupt the entry of a command. To remedy this situation, it also redraws a new prompt with the command that was being entered, complete up to the point where it was before the message was printed. This allows you to keep your place in the command and provide clean console output.

Which type value on the spanning-tree mode type global command enables the use of RSTP? -pvst -rapid-pvst -rpvst -rstp

-rapid-pvst Explanation: Of the four answers, only pvst and rapid-pvst are valid options on the command. Of those, the rapid-pvst option enables Rapid Per VLAN Spanning Tree (RPVST+), which uses RSTP. The pvst option enables Per VLAN Spanning Tree (PVST) which uses STP, not RSTP. The other two options, if attempted, would cause the command to be rejected because the option does not exist.

Which OSPF command will display the OSPF network type that a specific interface uses? -show ip interface g0/1 ospf -show ospf interface g0/1 -show ip ospf interface g0/1 -show ip ospf g0/1

-show ip ospf interface g0/1 Router1# show ip ospf interface g0/1 GigabitEthernet0/1 is up, line protocol is up Internet Address 10.10.10.1/24, Area 0 Process ID 1, Router ID 192.168.1.1, Network Type BROADCAST, Cost: 10 Transmit Delay is 1 sec, State BDR, Priority 1

Which of the following commands list the OSPF neighbors off interface serial 0/0? (Choose two answers.) -show ip ospf neighbor -show ip neighbor -show ip ospf neighbor serial 0/0 -show ip interface -show ip ospf interface brief Select 2 answers

-show ip ospf neighbor -show ip ospf neighbor serial 0/0 Explanation: Of the three wrong answers, two are real commands that simply do not list the OSPF neighbors. show ip ospf interface brief lists interfaces on which OSPF is enabled but does not list neighbors. show ip interface lists IPv4 details about interfaces, but none related to OSPF. One incorrect answer, show ip neighbor, is not a valid IOS command.

Which of the following commands do not list the IP address and mask of at least one interface? (Choose two answers.) -show interfaces -show version -show ip interface brief -show running-config -show protocols type number Select 2 answers

-show version -show ip interface brief Explanation: The show ip interface brief command lists all the interface IPv4 addresses but none of the masks. The show version command lists none of the IP addresses and none of the masks. The other three commands list both the address and mask.

Suppose you need to connect two new Cisco APs to a switched network. One is an autonomous AP, the other a lightweight AP. The APs will be used to provide four WLANs that map to four VLANs. Which of the following correctly describes the wired network link that connects to the autonomous and lightweight APs, respectively? -access mode, access mode -trunk mode, trunk mode -trunk mode, access mode -access mode, trunk mode

-trunk mode, access mode Explanation: The autonomous AP will need a wired link configured in trunking mode so that all four VLANs can be carried over the single link. The lightweight AP needs its wired connection configured in access mode. The same four VLANs will be available at the AP, but they will be carried between the WLC and AP over CAPWAP tunnels.