Patent ID: 7580359
Filing Date: 2009-08-25
Classification: H04L

Abstract:
1. A method for adding a new path and converting an existing path into an updated path, the new path, the existing path, and the updated path traversing links from a source node toward a terminal node in a network, the method comprising: transmitting a forward entity from the source node along forward links through the network from the source node toward the terminal node to determine links for the new path; when the forward entity encounters a node having insufficient capacity on a forward link exiting the node, the forward link sending data downstream toward the terminal node, determining whether the existing path has at least one reverse link entering the node, wherein the at least one reverse link has at least one Label Switched Path (LSP) coming into the node, the at least one LSP sending data front the source node to the terminal node; when the existing path has at least one reverse link entering the node, transmitting the forward entity backward along the at least one reverse link toward the source node until the forward entity encounters a node having sufficient capacity on a forward link exiting the node; transmitting the forward entity on the forward link having sufficient capacity to the terminal node; determining whether the existing path can be moved from the forward link having insufficient capacity to include the forward link having sufficient capacity; when the existing path can be moved, moving LSP corresponding to the existing path from the at least one reverse link to create an updated path for the existing path, the updated path using the forward link having sufficient capacity, thereby converting the forward link having insufficient capacity into a forward link having newly available capacity for use by the new path; and creating the new path including the forward link having newly available capacity.