Which statement is correct regarding MP-BGP?
A.
MP-BGP can indicate whether an advertised prefix (NLRI) is to be used for unicast
routing, multicast RPF checks or for both using different SAFIs.
B.
MP-BGP uses a single BGP table to maintain all the unicast prefixes for unicast
forwarding and all the unicast prefixes for RPF checks.
C.
MP-BGP can be used to propagate multicast state information, which eliminates the need
to use PIM for building the multicast distribution trees.
D.
MP-BGP enables BGP to carry IP multicast routes used by MSDP to build the multicast
distribution trees.
Explanation:
Protocol Independent Multicast
Protocol Independent Multicast (PIM) is a routing protocol designed to send and receive
multicast routing updates. Proper operation of multicast depends on knowing the unicast
paths towards a source or an RP. PIM relies on unicast routing protocols to derive this
reverse-path forwarding (RPF) information. As the name PIM implies, it functions
independently of the unicast protocols being used. PIM relies on the Routing Information
Base (RIB) for RPF information. If the multicast subsequent address family identifier (SAFI)
is configured for Border Gateway Protocol (BGP), or if multicast intact is configured, a
separate multicast unicast RIB is created and populated with the BGP multicast SAFI routes,
the intact information, and any IGP information in the unicast RIB. Otherwise, PIM gets
information directly from the unicast SAFI RIB. Both multicast unicast and unicast databases
are outside of the scope of PIM.The Cisco IOS XR implementation of PIM is based on RFC 4601 Protocol Independent
Multicast – Sparse
Mode (PIM-SM): Protocol Specification. For more information, see RFC 4601 and the
Protocol Independent Multicast (PIM): Motivation and Architecture Internet Engineering
Task Force (IETF) Internet draft