Patent ID: 8549176

Claim:
A method for dynamically retrieving inter-domain reachability information from a target node located internal to a remote domain along a traffic engineering (TE) label switched path (LSP) that spans multiple domains in a computer network, the method comprising: requesting the inter-domain reachability information from the target node of the TE-LSP that spans multiple domains, over a network interface of a head-end node of the TE-LSP that spans multiple domains, wherein the head-end node is located internal to a local domain and the target node is located internal to the remote domain, and wherein the inter-domain reachability information includes at least one address prefix reachable from the target node utilizing the TE-LSP that spans multiple domains; returning the requested inter-domain reachability information from the target node to the head-end node; calculating, at the head-end node, a shadow table of the head-end node that includes one or more routes reachable utilizing the TE-LSP to the target node, based on the requested inter-domain reachability information; and merging, at the head-end node, the one or more routes included in the shadow table that are reachable utilizing the TE-LSP to the target node, with non-TE-LSP routes in a routing table that are reachable not utilizing the TE-LSP by inserting the one or more of the routes included in the shadow table into the routing table of the head-end node.