Patent ID: 8804722

Claim:
A computer-implemented method in which a computer system performs operations comprising: configuring each of a plurality of Shortest Path Bridging (SPB) edge routers of an SPB network connected to a Protocol Independent Multicast (PIM) based access network as a Rendezvous Point (RP); receiving at a first one of the plurality of RPs a first message; in response to the receiving a first message, the first one of the plurality of RPs forming a first data structure, the first data structure including multicast sender information comprising: Intermediate System to Intermediate System Internet Protocol Multicast Type, Length, Value (ISIS IPMC TLV) data structure; flooding, by the first one of the plurality of RPs, the SPB network with a second message containing the first data structure; allocating, by the first one of the plurality of RPs, an identifier (ISID) to the multicast stream and sending a second data structure with sender information; for an edge router with multicast receive interest, responding with the second data structure with multicast receive interest information; and wherein a receiver in a second network external to the SPB network has knowledge of devices in a first network external to the SPB network such that multicast traffic is able to be routed between different networks connected to the SPB network.