Four routers are running IS-S and the adjacency relation has been established, and the level of area number and router are marked as shown, which of the following statements are true?

Four routers are running IS-S and the adjacency relation has been established, and the level of area number and router are marked as shown, which of the following statements are true?

A . Both R2 and R3 will have the Level-1’s LSP of ATT set
B . R1 does not have the LSP generated by R4, so R1 can only communicate with R4 through the default route
C . Both R2 and R3 will have the Level-1’s LSP of ATT set
D . R2 and R3 learn default routes from each other, and there is a routing loop in this network

View Answer

Answer: A