Multiprotocol BGP-Based Multicast VPNs: Next-Generation

Multiprotocol BGP-based multicast VPNs (also referred to as next-generation Layer 3 VPN multicast) constitute the next evolution after dual multicast VPNs (draft-rosen) and provide a simpler solution for administrators who want to configure multicast over Layer 3 VPNs.

The main characteristics of multiprotocol BGP-based multicast VPNs are:

• They extend Layer 3 VPN service (RFC 2547) to support IP multicast for Layer 3 VPN service providers
• They follow the same architecture as specified by RFC 2547 for unicast VPNs. Specifically, BGP is used as the control plane.
• They eliminate the requirement for the virtual router (VR) model, which is specified in Internet draft draft-rosen-vpn-mcast, Multicast in MPLS/BGP VPNs, for multicast VPNs.
• They rely on RFC-based unicast with extensions for intra-AS and inter-AS communication.

Multiprotocol BGP-based VPNs are defined by two sets of sites: a sender set and a receiver set. Hosts within a receiver site set can receive multicast traffic and hosts within a sender site set can send multicast traffic. A site set can be both receiver and sender, which means that hosts within such a site can both send and receive multicast traffic. Multiprotocol BGP-based VPNS can span organizations (so the sites can be intranets or extranets), can span service providers, and can overlap.

Site administrators configure multiprotocol BGP-based VPNs based on customer requirements and the existing BGP and MPLS VPN infrastructure. For more detailed information about multiprotocol BGP-based VPN configuration statements, see the Junos VPNs Configuration Guide.