Patent ID: 8355347
Filing Date: 2013-01-15
Classification: H04L

Abstract:
1. A method comprising: at a first root node of a first Multipoint-to-Multipoint (MP2MP) Multi-Protocol Label Switching (MPLS) tree, advertising to a second root node of a second MP2MP MPLS tree a first label for the second root node to use to send multicast traffic to the first MP2MP MPLS tree, the first root node being distinct from the second root node and the first MP2MP MPLS tree being distinct from the second MP2MP MPLS tree; at the first root node, receiving a second label from the second root node for the first root node to use to send multicast traffic to the second MP2MP MPLS tree; and carrying out communications between the first MP2MP MPLS tree and the second MP2MP MPLS tree using the first label and the second label, wherein carrying out communications includes: wherein the method further comprises establishing a directed Label Distribution Protocol (LDP) session between the first root node and the second root node over a first Point-to-Point (P2P) Label Switched Path (LSP) and a second P2P LSP; wherein advertising to the second root node the first label includes sending the first label over the directed LDP session via the first P2P LSP; and wherein receiving the second label from the second root node includes receiving the second label over the directed LDP session via the second P2P LSP; wherein the first MP2MP MPLS tree is under control of a first service provider; wherein the second MP2MP MPLS tree is under control of a second service provider, the first service provider and the second service provider being distinct; and wherein establishing the directed LDP session between the first root node and the second root node over the first P2P LSP and the second P2P LSP includes establishing the directed LDP session as an inter-domain session between the first service provider and the second service provider.