Patent ID: 7860104

Claim:
A method of establishing a point-to-multipoint (P2MP) tunnel across a network between an upstream router and two or more downstream routers using the Resource Reservation Protocol with Traffic Engineering (RSVP-TE), the method comprising: outputting to the upstream router RSVP-TE advertisements that include upstream label assignment capability indications from one or more of the downstream routers of the tunnel, wherein the upstream assignment capability indications from the downstream routers indicate whether the respective downstream router is capable of supporting upstream assigned labels; receiving a RSVP PATH message having a label object with the at least one of the downstream routers, wherein the label object specifies an upstream assigned label allocated to the downstream routers of the tunnel that output the RSVP-TE advertisements carrying the upstream label assignment capability indications; outputting, from the at least one of the downstream routers to the upstream router, an RSVP RESV message without including any downstream assigned labels when the downstream router supports the type of label object included in the RSVP PATH message and is able to process the upstream assigned label; outputting, from the at least one of the downstream routers to the upstream router, an RSVP RESV message specifying an error when the downstream router does not support the type of label object included in the RSVP PATH message; and outputting, from the at least one of the downstream routers to the upstream router, an error message when the downstream router docs supports the type of label object included in the RSVP PATH message but the downstream router is unable to process the upstream assigned label.