US Patent 7558194 Virtual private network fault tolerance

Loss of connectivity on a mesh or virtual service (e.g., VPLS) may be restored by “stitching” a healing path between an affected node and another node on the mesh. Connectivity may be restored by “healing” or constructing an alternate path or connection between the affected node and the mesh. Unidirectional and bidirectional healing may be used to establish an alternate path between the affected node and the mesh. Additionally, removing pseudowire connections between the affected node and the mesh may be performed, while establishing a spoke connection to an advertised, available router to create a new connection or “stitch” together existing connections.