Question 1

Which of the following statements regarding OSPF is true?

Options :

A :

OSPF does not have an acknowledgement mechanism. Therefore, OSPF relies on the upper-layer protocol, TCP, for acknowledgement.

B : OSPF performs LSDB update every 30 minutes.

C : OSPF uses the Bellman-Ford algorithm, and each router independently runs this algorithm.

D : OSPF floods a LSU packet at an interval of 5s.

Answer: B

Question 2

When a routing policy is used to filter routes, which of the following route prefixes will be denied by the IP prefix below?

Options :

A : 1.1.1.1/26

B : 1.1.1.2/16

C : 1.1.1.1/32

D : 1.1.1.1/24

Answer: B,D

Question 3

TheAS_Pathattribute is an importantBGP attributeused for route selection. Which of the following statements aretrueabout this attribute?

Options :

A : When a route is advertised to an IBGP peer, the AS_Path remains unchanged.

B : This attribute can be used to prevent BGP routing loops.

C : This attribute is a well-known discretionary attribute that must be identified by all BGP routers.

D : BGP ignores AS_Confed_Sequence and AS_Confed_Set when calculating the AS_Path length.

Answer: A,B,D

Question 4

Similar to the OSPF DR, the IS-IS DIS needs to be elected on a broadcast network. However, the OSPF DR is preemptive by default, whereas the IS-IS DIS is not preemptive by default.

Options :

A : TRUE

B : FALSE

Answer: A

Question 5

VRRP is implemented based on thepriority and preemption functionsof VRRP routers.Which of the following statements is false about the VRRP solution?

Options :

A :

When preemption is enabled, a backup device preempts the master role if it has a higher priority than the current master.

B :

When preemption is disabled, a backup device does not preempt the master role even if it has a higher priority than the current master, provided that the current master is working properly.

C :

The master periodically sends VRRP Advertisement packets in the VRRP group to advertise its configurations such as the priority.

D :

Even if the VRRP device is the IP address owner, it still needs to participate in the election and does not directly transition to the Master state when receiving a message indicating that the interface goes Up.

Answer: D