About the OSPF calculating the shortest path tree phase, which of the following description is true?
Stub network segment is calculated in the first stage, router node and transit network segment arecalculated in the second stage
The routing node and Transiti network segment are calculated in the first stage, Stub network segmentis calculated in the second stage
The Stub segment is calculated in the first stage, the routing node is calculated in the second stage
The routing node is calculated in the first stage, the stub network segment is calculated in the secondstage
Correct answer: B
Question 2
About the description of IGMP Snooping working mechanism, which of the following statement is true?
The Layer 2 switch establishes and maintains the PIM routing table at Layer 2 by continuously monitoring IGMP messages
When IGMP Snooping is not running, multicast messages will be broadcast on the layer 2. After IGMP Snooping is running, the messages will no longer be broadcast on the layer 2, but will be multicast on the layer 2.
If the host sends an IGMP leave message, the switch will add the host to the corresponding multicast table
If a host sends an IGMP host report message, the switch will delete the multicast entry corresponding to the host
Correct answer: B
Question 3
How many Bytes is the minimum total length of the address in IS-IS?