A. The type of the two routers must be Level-1.

B. The type of one router can be Level-1-2, and that of the other can be Level-1.

C. The IS-IS process IDs of the two routers must be the same as each other.

D. The type of the two routers can keep the default settings.

A. Source IP address spoofing attacks.

B. Single-packet attacks

C. Man-in-the-middle attacks

D. Flood attacks

A. By default, WRR or WFQ is enabled on a router instead of PQ.

B. PQ and LLQ mechanisms are similar and can replace each other.

C. PQ can only be applied on serial interfaces and not on Ethernet interfaces.

D. PQ consumes massive storage and processing capabilities. Therefore, enabling PQ on low-end devices is not recommended.

A. R2 can receive LSPs from R1, but cannot add the routing information in the LSPs to the routing table

B. R2 can learn all routes advertised by R1

C. R2 can learn the routes 10.1.2.0/24 and 10.1.3.0/24

D. R2 can learn only the route 10.1.1.0/24

A. Shared tree

B. Dense Tree

C. Sparse Mode

D. PIM bidirectional

E. Source tree

F. Dense Mode