Multicast over Layer 3 VPNs
The JUNOS software provides support for multicast over Layer 3 virtual private networks (VPNs), as described in RFC 2547. The implementation is based on Section Two of the Internet Engineering Task Force (IETF) Internet draft Multicast in MPLS/BGP VPNs (draft-rosen-vpn-mcast-05.txt) and uses Protocol Independent Multicast (PIM) and Generalized Routing Encapsulation (GRE) tunneling. Initially, only PIM sparse mode was supported. In JUNOS Release 5.5, Layer 3 VPN multicast support is extended to include PIM dense mode.
This document assumes the reader is familiar with Layer 3 VPN operation on Juniper Networks routers, as well as standard PIM configurations. For more information on PIM and its usage in a Layer 3 VPN, see the JUNOS 5.5 Internet Software Configuration Guide: Multicast. For more information on Layer 3 VPN configuration, see the JUNOS 5.5 Internet Software Configuration Guide: VPNs. Both manuals are located at:
http://www.juniper.net/techpubs/software/junos/junos55.