Which four statements are correct regarding MSDP configurations and operations? (Choose four.)

Which four statements are correct regarding MSDP configurations and operations? (Choose four.)
A . The MSDP peers are also typically the RPs in respective routing domains.
B . SA messages are flooded to all other MSDP peers without any restrictions
C . On Cisco IOS, IOS-XE, and IOS-XR, the router can be configured to cache the SA messages to reduce the join latency
D . SA messages are used to advertise active sources in a domain
E . MSDP establishes neighbor relationships with other MSDP peers using TCP port 639
F .  MSDP peerings on Cisco IOS, IOS-XE, and IOS-XR support MD5 or SHA1 authentication

View Answer

Answer: A,C,D,E

Explanation:

http://www.cisco.com/en/US/docs/ios/ipmulti/configuration/guide/imc_msdp_im_pim_sm.html When MSDP is enabled, an RP in a PIM-SM domain maintains MSDP peering relationships with MSDPenabledrouters in other domains. This peering relationship occurs over a TCP connection, where primarily alist of sources sending to multicast groups is exchanged. MSDP uses TCP (port

639) for its peeringconnections. As with BGP, using point-to-point TCP peering means that each peer must be explicitlyconfigured. The TCP connections between RPs, moreover, are achieved by the underlying routing system. Thereceiving RP uses the source lists to establish a source path. If the multicast sources are of interest to adomain that has receivers, multicast data is delivered over the normal, source-tree building mechanismprovided by PIM-SM. MSDP is also used to announce

sources sending to a group. These announcementsmust originate at the RP of the domain.