As shown in the figure, MPLS/BGP IPVPN is deployed in the network. The MP-BGP neighbor relationship is established between PE1 and PE2 through the LoopbackD interface. After the configuration is completed, it is found that CE1 and CE2 cannot learn routes from each other. Use the command on PE2 to query neighbor information as shown in the figure. What is the most likely cause of the problem?

Which of the following series can be matched by the regular expression 100.S? (Multiple choice)

As shown in the figure, network administrator A on the R1 router, after modifying the MED value of the routing entry sent to R2 through the routing policy, can control the path of traffic entering AS100.

As shown in the figure:

In OSPF, ABR will convert all Type 7 LSAs in the NSSA area into Type 5 LSAs.