Abstract: Techniques are described for supporting PIM (Protocol Independent Multicast) Dense Mode (PIM-DM) and PIM Bootstrap Router (PIM-BSR) between different VPN sites of an IP VPN. A system includes a plurality of customer sites connected to a service provider network by provider edge (PE) routers that provide an IP VPN. A first one of the PE routers receives multicast traffic from a first one of the customer sites, wherein the multicast traffic is PIM (Protocol Independent Multicast) Dense Mode (PIM-DM) traffic for which no PIM join messages have been received by the first PE router from the other PE routers via BGP messages. A tunnel setup module of the first PE router is configured to automatically signal a provider tunnel through the service provider network upon receiving the PIM-DM multicast traffic without maintaining multicast state data for a multicast group associated with the PIM-DM multicast traffic.

Abstract: The subject matter of this specification can be implemented in, among other things, a method that includes receiving, at a first network device that is associated with an MVPN, an mtrace message that identifies a source device that is associated with the MVPN and that is separated from the first network device by an MPLS network. The method further includes determining an LSP from the first network device to a second network device that is associated with the MVPN and that is separated from the first network device by the MPLS network. The method further includes adding an IP header to the mtrace message, the IP header including a destination address set to a localhost loopback IP address. The method further includes encapsulating the mtrace message with an MPLS label stack that causes the encapsulated mtrace message to reach an instance of the MVPN on the second network device.