CCNA-Practice Test 5

Directions: For each of the following questions, select the choice that best answers the question or completes the statement.

1.	Look at the following diagram. A Class C address has been assigned for use in the network shown. Which subnet mask should be used to provide valid IP addresses for the number of hosts connected to router A, while wasting the fewest addresses? /24 /25 /26 /27 /28 /29 Figure 5-1
2.	Look at the following diagram. What will be the effect of replacing the hubs with switches in the network? (Choose two.) The number of collisions in each network will decrease. The available bandwidth that each host has will increase. The number of broadcasts that each host receives will decrease. The hosts will need to be re-addressed to place each host in a separate subnet. The gateway on each host will need to be changed to the IP address of the appropriate switch. Figure 5-2
3.	Your router discovers a remote network via a static route, EIGRP, and OSPF, and all the routing protocols are set to their default administrative distance. In this situation, which route will the router use to forward data to the newly discovered remote network? The router will use the static route. The router will use the OSPF route. The router will use the EIGRP route. The router will load-balance and use all three routes.
4.	The ISKI Corporation is configuring the serial interface of a Cisco router to connect to the router of a new ISP. After issuing the showinterfaces serial 0/0 command, it is observed that the interface is up and the line protocol is down. Which of the following commands will fix this problem? Border# copy running-config startup-config Border(config-if)# no shutdown Border(config-if)# encapsulation ppp Border(config-if)# no cdp enable Border(config-if)# ip address 192.168.1.1
5.	Choose three of the following that accurately describe RIP. RIPv1 does not support routing update authentication. RIPv2 does support routing update authentication. RIPv1 does not include subnet information in routing updates. RIPv2 does include subnet information in routing updates. RIPv1 does not support advertising routes across WANs. RIPv2 supports advertising routes across LANs as well as WANs. RIPv1 uses hold-down timers and split horizon to prevent routing loops. RIPv2 does not require hold-down timers or split horizon to prevent routing loops. RIPv1 sends periodic routing updates over the multicast IP address 224.0.0.10. RIPv2 sends periodic routing updates over the multicast IP address 224.0.0.9. RIPv1 does not support a network-addressing scheme in which hosts within the same major network have different subnet masks. RIPv2 does allow hosts within the same major network to have different subnet masks.
6.	Given a subnet mask of 255.255.255.224, which of the following addresses can be assigned to network hosts? (Chose three.) 15.234.118.63 92.11.178.93 134.178.18.56 192.168.16.87 201.45.116.159 217.63.12.192
7.	Look at the following diagram. RTR-1 has been properly configured with static routing. Which set of commands will configure RTR-2 with static routing to reach the RTR-1 networks? ip route 192.168.35.0 255.255.255.0 192.168.35.241 ip route 192.168.35.0 255.255.255.240 192.168.35.242 ip route 192.168.35.32 255.255.255.224 192.168.35.242 ip route 192.168.35.128 255.255.255.192 192.168.35.241 ip route 192.168.35.192 255.255.255.224 192.168.35.241 ip route 192.168.35.0 255.255.255.240 192.168.35.241 ip route 192.168.35.32 255.255.255.224 192.168.35.241 ip route 192.168.35.128 255.255.255.192 192.168.35.242 ip route 192.168.35.192 255.255.255.224 192.168.35.242 ip route 192.168.35.1 255.255.255.240 192.168.35.241 ip route 192.168.35.33 255.255.255.224 192.168.35.241 Figure 5-3
8.	Which of the following are key characteristics of PPP? (Choose three.) Can be used over analog circuits Maps a layer 2 address to layer 3 address Encapsulates several routed protocols Supports IP only Provides error correction Figure 5-4
9.	Look at the following diagram. Computer 1 is consoled into switch A. Telnet connections and pings run from the command prompt on switch A fail. Which of the following could cause this problem? Switch A is not directly connected to router JAX. Switch A does not have a default gateway assigned. Switch A does not have a CDP entry for switch B or router JAX. Switch A does not have an IP address. Port 1 on switch A should be an access port rather than a trunk port.
10.	What will an Ethernet switch do if it receives a unicast frame with a destination MAC that is not listed in the switch table? The switch will not forward unicast frames. The switch will forward the frame to a specific port. The switch will return a copy of the frame out the source port. The switch will remove the destination MAC from the switch table. The switch will forward the frame to all ports except the port on which it was received.
11.	In a spanning-tree topology, which of the following can you use to delimit the root port on each non-root switch? Path cost Lowest port MAC address VTP revision number Highest port priority number Port priority number and MAC address
12.	Which of the following is the reason you should configure port security on a switch? To prevent unauthorized Telnet access to a switch port To limit the number of layer 2 broadcasts on a particular switch port To prevent unauthorized hosts from accessing the LAN To protect the IP and MAC address of the switch and associated ports To block unauthorized access to the switch-management interfaces over common TCP ports
13.	Which type of EIGRP route entry describes a feasible successor? Backup route, stored in the routing table Primary route, stored in the routing table Backup route, stored in the topology table Primary route, stored in the topology table
14.	What can be done to secure the virtual terminal interface on a router? (Choose two.) Administratively shut down the interface. Physically secure the interface. Create an access list, and apply it to the virtual terminal interfaces with the access-group command. Configure a virtual terminal password and login process. Enter an access list, and apply it to the virtual terminal interfaces using the access-class command.
15.	Which characteristics are representative of a link-state routing protocol? (Choose three.) Provides a common view of the entire topology Exchanges routing tables with neighbors Calculates shortest path Utilizes event-triggered updates Utilizes frequent periodic updates
16.	Look at the following diagram. A network technician is asked to design a small network with redundancy. The exhibit represents this design, with all hosts configured in the same VLAN. What conclusion can be made about this design? This design will function as intended. Spanning-tree will need to be used. The router will not accept the addressing scheme. The connection between switches should be a trunk. The router interfaces must be encapsulated with the 802.1Q protocol. Figure 5-5
17.	Look at the following diagram. A network technician has issued the command show ip route. The technician is trying to discover why packets are not getting to the 172.16.2.0 network. What could be the problem? The Ethernet0 interface is down. The hop count of RIP is incorrect. The packets are being routed through the 10.0.0.0 network. There is no route to the 172.16.2.0 network in the routing table. The administrative distance of RIP is causing the packets to be dropped. R1# show ip route Codes: C-connected, S-Static, I-IGRP, R-RIP, M-mobile, B-BGP, D-EIGRP, EX-EIGRP external, O-OSPF, IA-OSPF inter area, E1-OSPF external type1, E2-OSPF external type 2, E-EGP i-IS-IS, L1-IS-IS level-1, L2-IS-IS level-2, *-candidate default, U-per-user static route Gateway of last resort is not set 172.16.0.0/24 is subnetted C 172.16.1.0 is directly connected, Ethernet0 R 10.0.0.0/8 [120/1] via 172.16.1.200, 00:00:01, Ethernet0 C 192.168.1.0/24 is directly connected, Loopback0 Figure 5-6
18.	Look at the following diagram. An internetwork has been configured as shown in the diagram, with both routers using EIGRP routing for AS 44. Users on the Branch router are unable to reach any of the subnets on the HQ router. Which of the following commands is necessary to fix this problem? Branch(config-router)# version 2 Branch(config-router)# no auto-summary Branch(config-router)# redistribute eigrp 44 Branch(config-router)# eigrp log-neighbor-changes Branch(config-router)# default-information originates Figure 5-7
19.	In which of these situations will numerous copies of the same unicast frame be transmitted over a switched LAN? During high traffic periods After broken links are re-established When upper-layer protocols require high reliability In an improperly implemented redundant topology When a dual ring topology is in use
20.	Look at the following diagram. Which two values indicate that this router output refers to a WAN interface? (Choose two.) MTU size Bandwidth IP address Reliability Encapsulation Keep alive value Figure 5-8
21.	Look at the following diagram. A router interface is being configured for Frame Relay. However, as the exhibit shows, the router will not accept the command to configure the LMI type. What is the problem? The interface does not support Frame Relay connections. The interface does not have an IP address assigned to it yet. The interface requires that the no shutdown command be configured first. The interface requires that the encapsulation frame-relay command be configured first. Router(config)# interface serial 0/0 Router(config-if)# frame-relay Imi-type cisco ^ % Unrecognized command Router(config-if)# frame-relay ? % Unrecognized command Figure 5-9
22.	All WAN links inside the ABC Corporate network use PPP with CHAP for authentication security. Which command displays the CHAP authentication process as it occurs between two routers in the network? show CHAP authentication show interface serial0 debug PPP authentication debug CHAP authentication show PPP authentication chap
23.	Look at the following router output obtained via the show frame-relay map command, and choose the answer that best describes what the term dynamic means: Vine#show frame-relay map Serial0/0 (up): ip 192.168.10.1 dlci 16 (0x64, 0x1840), dynamic Broadcast, status defined, active The Serial0/0 interface is passing traffic. The DLCI 16 was dynamically allocated by the router. The Serial0/0 interface acquired the IP address of 192.168.10.1 from a DHCP server. The DLCI 16 will be dynamically changed as required to adapt to changes in the Frame Relay cloud. The mapping between DLCI 16 and the end station IP address 192.168.10.1 was learned through inverse ARP.
24.	The Winery Coop has five branches throughout Napa and Sonoma, and the company wants to build a WAN to give it a completely meshed environment with a minimum of 512Kbps throughput. It also needs the most cost-effective solution. Which WAN service should the company choose? Frame Relay Leased lines ISDN BRI ATM PPP
25.	Based on the following switch output, how did the switch receive the MAC table entry for 0012.7f4b.6882? Code Listing 5-1 Switch#sh mac address-table Mac Address Table ------------------------------------------- Vlan Mac Address Type Ports ---- ----------- -------- ----- All 0005.dccb.d740 STATIC CPU All 0100.0ccc.cccc STATIC CPU All 0100.0ccc.cccd STATIC CPU All 0100.0cdd.dddd STATIC CPU 1 000a.f467.9e80 DYNAMIC Fa0/11 1 0010.7b7f.c2b0 DYNAMIC Fa0/11 1 0012.7f4b.6880 DYNAMIC Fa0/11 1 0012.7f4b.6881 DYNAMIC Fa0/11 1 0012.7f4b.6882 DYNAMIC Fa0/11 1 0030.80dc.460b DYNAMIC Fa0/11 1 0030.9492.a5dd DYNAMIC Fa0/2 1 00d0.58ad.05f4 DYNAMIC Fa0/1 Total Mac Addresses for this criterion: 12 Switch# It was forwarded from an adjacent switch. It was entered from the configuration mode. It was acquired by a broadcast from the switch. It represents a MAC address of the switch.
26.	You're adding a new router into an OSPF network, and the networks connected to your new router aren't showing up in the routing tables of the other OSPF routers. You have the subnets 10.10.10.0/24 and 10.11.11.0/24. What should your OSPF configuration be if you want to create one network entry and place both subnets into area 0? Router(config)# router ospf 1 Router(config)# network 10.0.0.0 255.0.0.0 area 0 Router(config)# router ospf 1011 Router(config)# network 10.0.0.0 255.255.255.0 area 0 Router(config)# router ospf 1 Router(config)# network 10.0.0.0 0.0.0.255 area0 Router(config)# router ospf 1 Router(config)# network 10.0.0.0 0.0.0.255 area 0
27.	Which of the following commands configures a default route to any destination network not found in the routing table? Router(config)# ip default- route 0.0.0.0 255.255.255.255 s0 Router(config)# ip route 0.0.0.0 255.255.255.255 s0 Router(config)# ip default- route 0.0.0.0 s0 Router(config)# ip route 0.0.0.0 0.0.0.0 s0 Router(config)# ip route any any e0
28.	Look at the following diagram. After the router interfaces shown in the diagram have been configured, it is discovered that hosts in the Branch LAN cannot access the Internet. Further testing reveals additional connectivity issues. What will fix this problem? Change the address of the Branch router LAN interface. Change the address of the Branch router WAN interface. Change the subnet mask of the HQ router LAN interface. Change the address of the HQ router LAN interface. Change the address of the HQ router interface to the Internet. Change the subnet mask of the HQ router interface to the Internet. Figure 5-10
29.	You need to keep the hosts with the subnet address 172.16.24.0/21 in the VLAN from accessing Telnet services. Which of the following provides the missing answers in this command? access-list 110 deny protocol 172.16.24.0 mask any eq port Port 23 Port 80 Protocol IP Protocol TCP Wildcard 0.0.3.255 Mask 0.0.7.255
30.	Look at the following diagram. The router has been configured to provide communication between the VLANs. Which IOS commands are required to configure switch port fa0/1 to establish a link with router R1 using the IEEE standard protocol? (Choose three.) Switch(config)# interface fastethernet 0/1 Switch(config)# switchport mode access Switch(config)# switchport mode trunk Switch(config)# switchport access vlan 1 Switch(config)# switchport trunk encapsulation isl Switch(config)# switchport trunk encapsulation dot1q Figure 5-11
31.	Why would you use this command? ip route 0.0.0.0 0.0.0.0 serial0/0 It configures a router to send all packets out interface serial0/0. It configures a router to block routing updates from being sent out interface serial0/0. In configures a router as a firewall, blocking all unauthorized packets from exiting serial0/0. It configures a router to send all packets for unknown destination networks out interface serial0/0. It configures a router to drop all packets for which the destination network is unknown.
32.	An inbound access list has been configured on a serial interface to deny packet entry for TCP and UDP ports 21, 23, and 25. What types of packets will be permitted by this ACL? (Choose three.) FTP Telnet SMTP DNS HTTP POP3
33.	You're faced with reconfiguring a Catalyst 2950. Pick three steps that will guarantee the old configuration is erased. Erase flash. Restart the switch. Delete the VLAN database. Erase the running configuration. Erase the startup configuration. Modify the configuration register.
34.	If you were implementing VLSM on a network with a single Class C IP address, which subnet mask would you use to create the most effective point-to-point serial link? 255.255.255.0 255.255.255.240 255.255.255.248 255.255.255.252 255.255.255.254
35.	A network administrator has installed a new router in the Lisbon office and is unable to back up the IOS image of the new router to a TFTP server located in the Gibraltar office. Given the network diagram, identify the source of the problem. Incorrect default gateway of the TFTP server Incorrect subnet mask of the TFTP server Incorrect IP address of the TFTP server Incorrect IP address on E0 of the Gibraltar router Incorrect subnet mask on the Lisbon router Figure 5-12
36.	In which spanning-tree states does a switch port learn MAC addresses? (Choose two.) Blocking Listening Forwarding Learning Relaying
37.	You've subnetted your client's internetwork using 29 bits. You now need to configure an extended access list to control access to a whole subnetwork. To achieve this, which of the following wildcard masks should you use? 255.255.255.224 255.255.255.248 0.0.0.224 0.0.0.8 0.0.0.7 0.0.0.3
38.	Look at the following diagram. A network technician is troubleshooting a connectivity problem on R2. The technician enters the show cdp neighbors command at the R2 console. If the network is composed only of Cisco devices, for which devices should entries be displayed? R1 SW-B and R1 SW-B, R1, and SW-C R3, SW-B, R1, and SW-C SW-A, R3, SW-B, R1, and SW-C Host A, SW-A, R3, SW-B, R1, and SW-C Figure 5-13
39.	Look at the following output, and pick the option that solves the problem of why Serial0/0 won't respond to a ping from a machine on the FastEthernet0/0 LAN. Code Listing 5-2 Napa#sh ip interface brief Interface IP-Address OK? Method Status Protocol Ethernet0/0 192.168.10.1 YES NVRAM up up Serial0/0 192.168.15.1 YES NVRAM administratively down down Serial0/1 192.168.16.1 YES NVRAM up up Serial0/2 unassigned YES NVRAM administratively down down Router# Enable the Serial0/0 interface. Correct the IP address for Serial0/0. Correct the IP address for FastEthernet0/0. Change the encapsulation type on Serial0/0. Enable autoconfiguration on the Serial0/0 interface.
40.	A network administrator wants the text "Unauthorized access prohibited!" to be displayed before the login prompt when someone tries to initiate a Telnet session to a router. Which command can be used to configure this message? login banner x Unauthorized access prohibited! x banner exec y Unauthorized access prohibited! y banner motd x Unauthorized access prohibited! x login message "Unauthorized access prohibited!" vty motd "Unauthorized access prohibited!" vty 0 4 banner "Unauthorized access prohibited!"
41.	Look at the following diagram. The two connected ports on the switch are not turning orange or green. What will be the most effective steps to troubleshoot this Physical layer problem? (Choose three.) Ensure that the Ethernet encapsulations match on the interconnected router and switch ports. Ensure that cables A and B are straight-through cables. Ensure that cable A is plugged into a trunk port. Ensure that the switch has power. Reboot all the devices. Reseat all the cables. Figure 5-14
42.	Choose two of the following options that accurately describe the tasks that the OSPF Hello protocol performs. It provides dynamic neighbor discovery. It detects unreachable neighbors in 90-second intervals. It maintains neighbor relationships. It negotiates correctness parameters between neighboring interfaces. It uses timers to elect the router with the fastest links as the designated router.
43.	Which type of EIGRP route entry describes a feasible successor? Backup route, stored in the routing table Primary route, stored in the routing table Backup route, stored in the topology table Primary route, stored in the topology table
44.	What does a layer-2 switch do if it receives a frame with a destination MAC address that is not found in its MAC address table? The frame is dropped. The frame is addressed with a broadcast MAC address and sent out all ports. The frame is sent out all ports except the receiving port. An ARP request is sent out all ports except the receiving port. A destination-unreachable message is sent back to the source address.
45.	You've created the access list shown below and applied it to an interface. Which of the following are denied based on the access list? access-list 107 deny tcp 207.16.12.0 0.0.3.255 any eq http access-list 107 permit ip any any source IP:207.16.32.14, destination application: http source IP:207.16.15.9, destination port: 23 source IP:207.16.14.7, destination port: 80 source IP:207.16.13.14, destination application: http source IP:207.16.16.14, destination port: 53
46.	On three different occasions, an administrator configured a router and, after testing the configuration, saved it to NVRAM by issuing the copy running-config startup-config command. After each successful save, the administrator issued the reload command. Each time, when the router restarted, the router appeared to have the default blank configuration. What could cause such results? The boot system commands were left out of the configuration. The NVRAM is corrupted. The configuration register setting is incorrect. The upgraded IOS just loaded is not compatible with the hardware. The upgraded configuration is not compatible with the hardware platform.
47.	The OSPF Hello protocol performs which of the following tasks? (Choose two.) It provides dynamic neighbor discovery. It detects unreachable neighbors in 90-second intervals. It maintains neighbor relationships. It negotiates correctness parameters between neighboring interfaces. It uses timers to elect the router with the fastest links as the designated router. It broadcasts hello packets throughout the internetwork to discover all routers that are running OSPF.
48.	What is the purpose of this command? ip route 0.0.0.0 0.0.0.0 serial0/0 It configures a router to send all packets out interface serial0/0. It configures a router to block routing updates from being sent out interface serial0/0. It configures a router as a firewall, blocking all unauthorized packets from exiting serial0/0. It configures a router to send all packets for unknown destination networks out interface serial0/0. It configures a router to drop all packets for which the destination network is unknown.
49.	Choose the three services that use TCP. DHCP SMTP SNMP FTP HTTP TFTP
50.	Look at the following diagram. How should the FastEthernet0/1 ports on the 2950 model switches that are shown in the exhibit be configured to allow connectivity between all devices? The ports only need to be connected by a crossover cable. SwitchX(config)# interface fastethernet 0/1 SwitchX(config-if)# switchport mode trunk SwitchX(config)# interface fastethernet 0/1 SwitchX(config-if)# switchport mode access SwitchX(config-if)# switchport access vlan 1 SwitchX(config)# interface fastethernet 0/1 SwitchX(config-if)# switchport mode trunk SwitchX(config-if)# switchport trunk vlan 1 SwitchX(config-if)# switchport trunk vlan 10 SwitchX(config-if)# switchport trunk vlan 20 Figure 5-15
51.	Look at the following diagram. What does the number 782 represent? Administrative distance Delay to the destination Cost of the route Hop count Figure 5-16
52.	When setting up Frame Relay for point-to-point subinterfaces, which of the following must not be configured? Frame Relay encapsulation on the physical interface Local DLCI on each subinterface IP address on the physical interface Subinterface type as point-to-point
53.	What is the purpose of the OSPF router ID in a DR/BDR election? It is used with the OSPF priority values to determine which OSPF router will become the DR or BDR in a point-to-point network. It is used with the OSPF priority values to determine which interface will be used to form a neighbor relationship with another OSPF router. It is used with the OSPF priority values to determine which router will become the DR or BDR in a multiaccess network. It is used to determine which interfaces will send Hello packets to neighboring OSPF routers.
54.	Select the statements that correctly describe full- or half-duplex Ethernet operation. (Choose two.) Full-duplex Ethernet uses CSMA/CD to prevent collisions. Full-duplex Ethernet uses two pairs of wires for data. An Ethernet hub can operate at half or full duplex. Half-duplex Ethernet uses a loopback circuit to detect collisions. A 10Mbps full-duplex Ethernet card allows 20Mbps for transmitting data and 20Mbps for receiving data.
55.	Of the choices below, which one is needed for connectivity in a Frame Relay network if Inverse ARP isn't operational? frame-relay arp frame-relay map frame-relay interface dlci frame-relay Imi-type

Answers

1.	C Explanation: C. A /26 mask allows for up to 62 hosts.
2.	A, B Explanation: A, B. Switches decrease the number of collisions and increase the effective bandwidth each individual host has.
3.	A Explanation: A. Administrative Distance (AD) is the value a router uses to differentiate between routing information. Each routing protocol is given a value; a static route has the best AD: 1 (the lower, the better; only a directly connected network is better, with an AD of 0).
4.	C Explanation: C. The default encapsulation is HDLC on Cisco routers, which is proprietary. Changing to PPP encapsulation (amore universal standard) is the most likely choice to resolve the up/down issue here.
5.	A, B, F Explanation: A, B, F. RIPv1 is a classful routing protocols, which means all masks on every host in the network must be exactly the same. RIPv1 sends broadcasts, and RIPv2 uses multicast: 224.0.0.9. RIP has many loop-avoidance mechanisms, some of which are split-horizon and hold-down timers. Others include route poison, setting infinity, and triggered updates. RIPv2 supports authentication as well; v1 does not.
6.	B, C, D Explanation: B, C, D. With a /27 mask, you must ensure that the last 5 bits are not all ones (broadcast address) or zeros (network address). A and E are both all ones, and F is all zeros.
7.	D Explanation: D. The correct routes are for the two networks (192.168.35.0 and 192.168.35.32 along with correct masks) via the RTR-1 serial interface IP address.
8.	A, C, E Explanation: A, C, E. PPP can be used over analog circuits, supports multiple routed (layer 3) protocols, and uses a CRC to provide error correction.
9.	D Explanation: D. Telnet and ping require that switch A has a valid IP configuration. The default gateway and CDP are not relevant here. Also, a trunk port is not required to ping or telnet.
10.	E Explanation: E. When the destination MAC of a unicast frame is unknown, the switch forwards the frame on all ports except the one on which it was received.
11.	A Explanation: A. Path cost is the first value that is used to determine which port should be blocking or forwarding. If path cost does not differentiate, then bridge id and port id can be used.
12.	C Explanation: C. Port security can prevent unauthorized hosts from accessing the LAN. It can be configured with a maximum number of MAC addresses per port, or to allow only specifically configured MACs access.
13.	C Explanation: C. A feasible successor is stored in EIGRP's topology table, which holds all links known in the autonomous system. A successor route is copied from the topology table and placed in the routing table, which is then used by IP to route packets. The feasible successor is the backup route to the successor route.
14.	D, E Explanation: D, E. The virtual terminal can be secured with a password. Additionally, you can control source IP addresses that have access to the VTY using a standard IP access list and the access-class command.
15.	A, C, D Explanation: A, C, D. Link-state routing protocols calculate a view of the entire topology, calculate shortest paths, and use event-triggered (not periodic) updates.
16.	C Explanation: C. You cannot assign two interfaces on the same router addresses in the same subnet, or IOS will generate an error.
17.	D Explanation: D. Without a route to the destination or a default route, the router will drop packets.
18.	B Explanation: B. The no auto-summary command must be used when subnetworks are not contiguous.
19.	D Explanation: D. If you have switches connected with dual links, and STP is not running, then you will have broadcast storms, multiple frame copies, and MAC table instability.
20.	B, E Explanation: B, E. The bandwidth is below that of any LAN interface, and the encapsulation (HDLC) is not used on LAN interfaces.
21.	D Explanation: D. Until the interface is configured with Frame Relay encapsulation, none of the more specific Frame Relay commands will be functional.
22.	C Explanation: C. You must use a debug command show the authentication as it happens. In this case, the "debug ppp authentication" command.
23.	E Explanation: E. Inverse ARP is the automatic process of finding a DLCI from a known IP address. If this function is not available, then the mapping of the DLCI to the IP address must be done manually through the frame-relay map command.
24.	A Explanation: A. The bandwidth requirement and the fact that it is to be cost effective make Frame Relay the only real choice.
25.	A Explanation: A. The best answer is that the MAC address was forwarded from another switch, because port Fa0/11 has many MAC addresses associated with it.
26.	D Explanation: D. Although answer C is close, only answer D is correct because you must have a space after the command area before listing the associated area.
27.	D Explanation: D. A default route is a static route where the destination network and mask are all zeros.
28.	B Explanation: B. The correct address should be 192.168.10.86.
29.	A, D, F Explanation: A, D, F. To answer this question, you must know what a /21 is. A /21 is 255.255.248.0, which is a block size of 8, wildcard of 7, in the third octet (wildcards are always one less than the block size). Telnet uses TCP at the Transport layer and is well-known port number 23.
30.	A, C, F Explanation: A, C, F. The interface must be configured as a trunk link, and the encapsulation must be specified.
31.	D Explanation: D. The ip route command with all zeros is a default route. Any traffic without a specific route is sent out the interface specified at the end of the command. A next hop can also be used with the command instead of the exit interface.
32.	D, E, F Explanation: D, E, F. Ports 21, 23, and 25 are associated with FTP, Telnet, and SMTP; and because the ACL is denying these packets, these protocols will not work.
33.	B, C, E Explanation: B, C, E. A typical router can be set back to factory defaults by erasing the startup-config in NVRAM and then reloading the device. However, a switch keeps the VLAN database in flash; so, that must also be deleted on a switch to set the switch back to factory defaults.
34.	D Explanation: D. A /30 or 255.255.255.252 provides only two hosts, regardless of the class of address, which is perfect for a point-to-point link.
35.	B Explanation: B. The subnet mask for a /28 network is 255.255.255.240, not 255.255.255.192.
36.	C, D Explanation: C, D. In the learning and forwarding states, a switchport can learn MAC addresses.
37.	E Explanation: E. First, you must know what a /29 is. The mask is 255.255.255.248, which means the block size is 8 in the fourth octet. A wildcard is always one less the block size, so the answer is 0.0.0.7.
38.	B Explanation: B. The R2 router should have SW-B and R1 as CDP neighbors.
39.	A Explanation: A. If an interface is administratively down, this means the interface is not enabled and must be enabled with the no shutdown command. All interfaces on a router are shut down by default.
40.	C Explanation: C. The banner motd command allows you to configure a message of the day.
41.	B, D, F Explanation: B, D, F. When the switchports fail to turn orange or green, it indicates a layer 1 problem. The wrong cable type or poorly seated cables can cause this issue, as can the switch not having power.
42.	A, C Explanation: A, C. A router running a link-state protocol uses hello packets to dynamically find neighbors and form adjacencies. Once an adjacency has been formed, the router uses link state advertisement (LSA) packets to exchange topology information and updates when changes occur.
43.	C Explanation: C. A feasible successor is stored in EIGRP's topology table, which holds all links known in the autonomous system. A successor route is copied from the topology table and placed in the routing table, which is then used by IP to route packets. The feasible successor is the backup route to the successor route.
44.	C Explanation: C. A LAN switch uses MAC addresses to segment the network into collision domains. The switch looks at the source MAC address of each frame received on a port and places this in a forward/filter table, also called the content addressable memory (CAM) table. If a frame is received and the destination hardware (MAC) address is not found in the CAM table, the frame is sent out all ports except the port it was received on.
45.	A, B, E Explanation: A, B, E. The wildcard in the mask is the key to the answer. 0.0.3.255 means that the third octet has a wildcard of 4. The 12 in the third octet means that the access-list will match 12, 13, 14, and 15, which make C and D permitted and A, B, E incorrect. B is wrong because the port number is wrong. A isn't in the correct block size; and E is 16, which is one more than the allowed block size.
46.	C Explanation: C. If the configuration register setting is incorrect, it is possible that the router will boot and ignore the startup-config.
47.	A, C Explanation: A, C. A router running a link-state protocol uses hello packets to dynamically find neighbors and form adjacencies. Once an adjacency has been formed, the router uses link state advertisement (LSA) packets to exchange topology information and updates when changes occur.
48.	D Explanation: D. This is known as a default route. It configures the router to send all packets for which the router does not have a specific route out the serial0/0 interface.
49.	B, D, E Explanation: B, D, E. SMTP, FTP, and HTTP are Application layer protocols that use TCP at the Transport layer. DHCP, SNMP, and TFTP all use UDP at the Transport layer.
50.	B Explanation: B. Specifying that the switchports are trunk links makes them able to carry all VLAN traffic. By default, they carry all VLANs.
51.	C Explanation: C. In this case, the 782 represents the OSPF cost of this route.
52.	C Explanation: C. When you are creating subinterfaces on a router, an IP address is not configured under the physical interface of the router. IP addresses can be configured only under the logical (subinterfaces) interfaces, or the network will not function.
53.	C Explanation: C. When OSPF is configured on a router, a router identification (RID) is created by using the highest IP address on any active interface at the moment of OSPF startup. The RID can be changed by creating a loopback interface, also called a logical interface. Routers use this RID to determine which router will be a designated router or backup-designated router in a broadcast or nonbroadcast multiaccess network.
54.	B, D Explanation: B, D. Full-duplex Ethernet uses two pairs of wires. In full-duplex Ethernet, there is no such thing as a collision. Half-duplex Ethernet does use CSMA/CD, does have collisions, and must use a loopback circuit to detect collisions.
55.	B Explanation: B. Inverse ARP is used to resolve an IP address to local DLCI number. If a router does not support IARP or is used on the network, a Frame Relay map must be configured for each PVC.