Point-to-multipoint (P2MP) LSPs are used to forward multicast VPN traffic across MPLS networks. A P2MP LSP is a TE tunnel that starts at a single PE source and ends at multiple PE destinations within a multicast VPN.
A P2MP LSP is composed of two or more RSVP-TE signaled subLSPs. A subLSP originates at the PE source and terminates at a particular PE destination.
P2MP LSPs for multicast VPNs are supported for intra-autonomous-system (AS) environments, but not for inter-AS environments.