100 Top CCNA Certification Multiple Choice Questions Answers

CCNA Certification Multiple Choice Questions:

1. When are link-state packets sent to neighbors?
A. every 30 seconds
B. every 180 seconds
C. after the holddown time expires
D. when a link goes up or down
E. when a routing loop occurs
ANS: D

2. Why is it difficult for routing loops to occur in networks that use link-state routing?
A. Each router builds a simple view of the network based on hop count.
B. Routers flood the network with LSAs to discover routing loops.
C. Each router builds a complete and synchronized view of the network.
D. Routers use hold-down timers to prevent routing loops.
ANS: C

3. What two statements correctly describe the link state routing process?
A. all routers in the area have link state databases
B. each router in the area floods LSPs to all neighbors
C. LSPs use the reserved multicast address of 224.0.0.10 to reach neighbors
D. routing loops are prevented by running the Diffusing Update Algorithm (DUAL).
E. Reliable Transport Protocol (RTP). is the protocol used by for the delivery and reception of LSPs
ANS: A

4. What action does a link-state router take immediately upon receipt of an LSP from a neighboring router?
A. floods the LSP to neighbors
B. calculates the SPF algorithm
C. runs the Bellman-Ford algorithm
D. computes the best path to the destination network
ANS: A

5. What two events will cause a link state router to send LSPs to all neighbors?
A. 30 second timer expires
B. whenever the network topology changes
C. immediately after the Bellman-Ford algorithm has run
D. immediately after the DUAL FSM has built the topology database
E. upon initial startup of router or routing protocol
ANS: E

6. Refer to the exhibit. What does JAX do with link-state packets from ORL?
A. sends out its updated routing table to both ORL and BOS routers
B. sends out the individual link-state packets out the interface connected to BOS
C. queries BOS to see if it has a better route
D. only adds it to the local routing table and performs no other actions
ANS: B

7. Which database or table must be identical on all link-state routers within an area in order to construct an accurate SPF tree?
A. routing table
B. adjacency table
C. link-state database
D. neighbor table
E. topology database
ANS: C

8. What feature do modern link-state protocols provide to minimize processing and memory requirements?
A. splitting routing topologies into smaller areas
B. assigning lower process priorities to route calculations
C. using update timers to restrict routing updates
D. strict split horizon rules to reduce routing table entries
ANS: A

9. What is the final step in the link state routing process?
A. successors are placed into the routing table
B. SPF computes the best path to each destination network
C. LSPs are flooded to all neighbors to converge the network
D. A DUAL algorithm is run to find the best path to destination networks
ANS: B

10. What are two advantages of using a link-state routing protocol instead of a distance vector routing protocol?
A. The topology database eliminates the need for a routing table.
B. Each router independently determines the route to each network.
C. Link-state protocols require less router processor power than distance vector protocols
D. After the inital LSP flooding, they generally require less bandwidth to communicate changes in a
topology.
E. Frequent periodic updates are sent to minimize the number of incorrect routes in the topological
database.
ANS: D

11. Which algorithm is run by link-state routing protocols to calculate the shortest path to destination networks?
A. DUAL
B. Dijkstra
C. Bellman-Ford
D. Diffie-Hellman
ANS: B

12. Which routers will router D receive hello packets?
A. A and E
B. B and C
C. A, B, C, and E
D. C only
ANS: B

13. What speeds up convergence in a network using link-state routing?
A. updates triggered by network changes
B. updates sent at regular intervals
C. updates sent only to directly connected neighbors
D. updates that include complete routing tables
ANS:  A

14. Refer to the exhibit. What kind of information would be seen in an LSP sent from router JAX to router ATL?
A. hop count
B. uptime of the route
C. cost of the link
D. a list of all the routing protocols in use
ANS: C

15. Which two routing protocols use Dijkstra’s shortest path first algorithm?
A. RIPv1
B. RIPv2
C. IS-IS
D. BGP
E. OSP
ANS: C,D

CCNA CERTIFICATION Objective Questions Pdf Free Download ::

16. Refer to the exhibit. Router B receives a packet with a destination address of 10.16.1.97. What will router B do?

A. drop the packet
B. forward the packet via the route to 10.16.1.0
C. forward the packet via the route to 10.16.1.64
D. use the default route
ANS:D

17. A network is converged and the routing tables are complete. When a packet needs to be forwarded, what is the first criterion used to determine the best path in the routing table?
A. the route with the smallest AD
B. the route with the longest address and mask match to the destination
C. the route with the highest bandwidth
D. the route with the best combination of AD and lowest cost
ANS: B

18. Refer to the exhibit. Which statement correctly describes this network?
A. they are dropped
B. sent to the default gateway
C. forward out interface Serial0/0/1
D. forward out interface FastEthernet 0/0
ANS: C

19. The following entry is displayed in the routing table: R 192.168.8.0/24 [120/2] via 192.168.4.1, 00:00:26, Serial0/0/1 What type of route is this?
A. a level 1 parent route
B. a level 1 supernet route
C. a level 1 ultimate network route
D. a level 2 child route
E. a level 2 ultimate child route
ANS: C

20. What determines if the router implements a classless route lookup process?
A. Child routes are present in the routing table.
B. A classless routing protocol has been configured on the router.
C. The command ip classless is enabled on the router.
D. Multiple routes with different masks to the same destination are in the routing table.
E. Routing table entries have a next-hop IP address and an exit interface for each child route.
ANS: C

21. Refer to the exhibit. How many routes in this output qualify for use as ultimate routes?
A. 3
B. 4
C. 5
D. 6
E. 7
ANS: E

22. Refer to the exhibit. Which statement correctly describes this network?
A. EIGRP is being used
B. There is at least one parent and one child route
C. 192.168.2.0, 192.168.3.0, and 192.168.4.0 networks are child routes
D. Traffic going to 172.16.3.0 will be directed to s 0/0/1
ANS: B

23. Refer to the exhibit. What protocol was used to distribute the routing information for the network 172.16.1.4?
A. RIPv1
B. RIPv2
C. EIGRP
D. OSPF
ANS: B

24. Refer to the exhibit. What can be determined from this output?
A. The router will have to perform recursive lookups to forward a packet destined for 192.168.2.213/24.
B. The parent route for these networks was removed from the routing table.
C. A route to 192.168.0.0/25 would be classified as a supernet route for the routes listed in the routing table.
D. All of the routes listed are network routes.
ANS: D

25. Refer to the exhibit. The graphic contains partial contents of the routing table on router E. Router E is running version 12.3 of the IOS and is configured for default routing behavior. Router E receives a packet to forward. Which route in the routing table will be searched first and why?
A. 172.16.1.0/25 because it is the first ultimate route
B. 0.0.0.0/0 because it is the lowest network number
C. 172.16.0.0/25 because it is the first level 1 route
D. 172.18.0.0/15 because it has the shortest mask
ANS: C

26. Refer to the exhibit. Router1 is running IOS version 12.2. What will the network administrator need to do so that packets for unknown child routes of 172.16.0.0/24 will not be dropped?
A. issue the ip default-network command
B. use a classful routing protocol such as RIPv1
C. enable either OSPF or ISIS as the routing protocol
D. issue the ip classless command
E. do nothing, ip classless is on by default
ANS: E

27. Refer to the exhibit. With the ip classless command issued, what will router R2 do with a packet destined for host 172.16.4.234?
A. drop the packet
B. send a packet out Serial 0/0/1
C. send the packet to network 0.0.0.0
D. send a packet out FastEthernet 0/0
ANS: B

28. A router has the following entries in its routing table:
S 192.168.0.0/24 [1/0] via 192.168.128.2
O 192.168.0.0/25 [110/2175] via 172.16.1.1, 00:02:15, FastEthernet0/1
D 192.168.0.0/25 [90/22455] via 172.16.2.2, 00:12:15, Serial0/0/0
R 192.168.0.0/26 [120/2] via 172.16.3.3, 00:00:15, Serial0/0/1
The router receives a packet that is destined for a host with the address 192.168.0.58.
Which route would this router use to forward the packet?
A. the static route
B. the OSPF route
C. the EIGRP route
D. the RIP route
ANS: D

29. Refer to the exhibit. What parent network will automatically be included in the routing table when the three subnets are configured on Router1?
A. 172.16.0.0/16
B. 172.16.0.0/24
C. 172.16.0.0/30
D. 172.16.1.0/16
E. 172.16.1.0/24
ANS: A

30. Refer to the exhibit. What subnet mask will Router1 apply to child routes of the 172.16.0.0/24 network?
A. 0.0.0.0
B. 255.255.0.0
C. 255.255.255.0
D. 255.255.255.255
ANS: C