Transporting multicast over MPLS backbone using virtual interfaces to perform reverse-path forwarding checks

摘要

A mechanism is provided in which multicast reverse path forwarding can be performed at a provider network egress edge router wherein core routers of the provider network are not configured to support multicast protocols or point-to-multipoint LSPs. An embodiment of the present invention provides for the creation of virtual interfaces in the egress edge router element during configuration of a multicast connection in response to a subscriber request. A virtual interface will be associated with an upstream ingress edge router element and that ingress edge router element is provided a label associated with the virtual interface. Such a label can then be included in datastream packets transmitted through the provider network and be used by reverse path forward checking at the egress edge router element to ascertain whether the multicast datastream is being received by the correct upstream interface.

主权项

1. A method comprising:
receiving a join message for a first multicast datastream and a reverse path forwarding label (RPF-label), wherein
the join message and the RPF-label are received at an ingress edge router of an MPLS (multiprotocol label switching) network; associating the RPF-label and the first multicast datastream; receiving a multicast packet of the first multicast datastream; and transmitting the multicast packet with the RPF-label, wherein
the multicast packet and the RPF-label are transmitted toward an egress edge router of the MPLS network,the RPF-label is associated with a first virtual interface at the egress edge router, andthe egress edge router is configured to perform an RPF check on the multicast packet using the first virtual interface as a receiving interface.