Signaling support for NG MVPNs
Two types of signaling support NG MVPNs:
- Interior BGP (iBGP) is extended to support multicast VPN for MPLS service signaling.
- Provider-tunnel (P-tunnel) signaling is used at the transport layer to carry multicast traffic. The Juniper-based implementation of NG MVPN uses the point-to-multipoint (P2MP) LSP for the P-signaling. The P2MP LSP is signaled by Resource Reservation Protocol with traffic engineering extensions (RSVP-TE)..Topology example for multicast VPN shows both unicast and multicast VPN traffic in an MPLS network.Topology example for multicast VPN
Figure 38 shows a network whereCustomer Ahas unicast traffic between all sites and multicast traffic between sites 1, 3, and 4. If PE-1 is an ingress edge router forCustomer A, unicast traffic from CE-A1 will be forwarded to one of the egress PEs. Multicast traffic, however, will be forwarded to all or some PEs, depending on how the multicast VPN is constructed.A multicast VPN is also constructed by a route target (RT). Both multicast VPN and unicast VPN for a customer may be constructed by the same RT, or the multicast VPN may be constructed by a different RT for the same customer.