Question

A network engineer is documenting an MPLS L3VPN deployment for a service provider. A junior colleague asks about the difference between the route distinguisher (RD) and the route target (RT) configured under a VRF. Which statement correctly describes their distinct roles in the MP-BGP VPNv4 architecture?

Accepted Answer

The RD makes customer prefixes unique across VRFs by prepending to the IPv4 address to form a VPNv4 prefix, while the RT is a BGP extended community that controls which VRFs import and export those routes.

Answer

The RD controls which VRFs import and export routes as an extended community, while the RT guarantees prefix uniqueness by prepending to the IPv4 address.

Answer

Both the RD and RT must be identical values to establish an MP-BGP VPNv4 session between PE routers.

Answer

The RD is used to assign MPLS labels per prefix, while the RT is used to distribute LDP bindings between PE and P routers.