Patent ID: 8111702

Claim:
A method comprising: receiving a transport tree building message at a first network element, wherein the first network element comprises a non-edge network element, the first network element comprises a processor, the transport tree building message comprises a forwarding equivalency class (FEC) comprising a transport tree identifier, the transport tree identifier comprises an opaque field and a non-opaque field, the opaque field is not interpreted by the first network element, the non-opaque field comprises a route property identifier, the route property identifier comprises a topology identifier as a result of an edge router modifying the FEC to include the topology identifier prior to the receiving, wherein the modifying is performed in response to the edge router receiving a multicast join message, and the topology identifier specifies a first topology of a plurality of topologies; and selecting an upstream next hop router in accord with the topology identifier, wherein the selecting is performed by the processor.