Patent ID: 7707307
Filing Date: 2010-04-27
Classification: H04L

Abstract:
1. A method of constructing a backup route for a primary route in a data communications network, said data communications network having as components nodes and links defining a network topology, said primary route including a first node, an adjacent component that is adjacent to the first node, and a second node that neighbors the adjacent component, the method comprising: (a) deriving from the topology a first set of nodes reachable from the first node without traversing the adjacent component, wherein the first set of nodes is different from the primary route; (b) deriving from the topology a second set of nodes from which the second node is reachable without traversing the adjacent component, wherein the second set of nodes is different from the primary route; (c) determining an intersection of the first set of nodes and the second set of nodes, the intersection comprising an intermediate node, wherein the intermediate node is neither the adjacent component nor in the primary route; and (d) constructing the backup route via the intermediate node; wherein the backup route includes the first node and the second node, but does not traverse the adjacent component; wherein the backup route is different from the first set of nodes and the second set of nodes; wherein the method is performed by one or more computing devices.