Ccna routing and Switching Complete Study Guide

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Answers to Assessment Test

12.  A.  If the state is STALE when the interface has not communicated within the neighbor 

reachable time frame. The next time the neighbor communicates, the state will be REACH. 

See Chapter 20 for more information.

13.  C.  There are two successor routes, so by default, EIGRP was load-balancing out s0/0 and 

s0/1. When s0/1 goes down, EIGRP will just keep forwarding traffic out the second link 

s0/0. s0/1 will be removed from the routing table. See Chapter 17 for more information.

14.  F.  There isn’t a lot to go on from with the output, but the only commands that provide 

the FD and AD are 

show ip eigrp topology and show ipv6 eigrp topology. The 

addresses in the output are link-local IPv6 addresses, so our answer is the latter. See  

Chapter 17 for more information.

15.  A, B, C, D.  Cisco has documented steps, according to the objectives, that you must go 

through when troubleshooting an adjacency. See Chapter 18 for more information.

16.  B, D, E.  In order for two OSPF routers to create an adjacency, the Hello and dead timers 

must match, and they must both be configured into the same area, as well as being in the 

same subnet. See Chapter 18 for more information.

17.  A.  The process starts by sending out Hello packets. Every listening router will then add 

the originating router to the neighbor database. The responding routers will reply with all 

of their Hello information so that the originating router can add them to its own neigh-

bor table. At this point, we will have reached the 2WAY state—only certain routers will 

advance beyond to this. See Chapter 19 for more information.

18.  C.  Referred to as summary link advertisements (SLAs), Type 3 LSAs are generated by area 

border routers. These ABRs send Type 3 LSAs toward the area external to the one where 

they were generated. See Chapter 19 for more information.

19.  B.  Authentication Header (AH) provides authentication of either all or part of the IP packet 

through the addition of a header that is calculated based on the values in the packet, but it 

doesn’t offer any encryption services. See Chapter 21 for more information.