"Previous RFCs specify the procedures necessary to allow IP multicast traffic to travel from one site to another within a BGP/MPLS IP VPN (Virtual Private Network). However@ it is sometimes desirable to allow multicast traffic whose source is in one VPN to be received by systems that are in another VPN. This is known as a ""Multicast VPN (MVPN) extranet"". This document updates RFCs 6513@ 6514@ and 6625 by specifying the procedures that are necessary in order to provide extranet MVPN service."
RFC 7900-2016 history
2016RFC 7900-2016 Extranet Multicast in BGP/IP MPLS VPNs