Route Finding in Communications Networks

摘要

PCT No. PCT/GB96/01912 Sec. 371 Date Feb. 23, 1998 Sec. 102(e) Date Feb. 23, 1998 PCT Filed Aug. 6, 1996 PCT Pub. No. WO97/06643 PCT Pub. Date Feb. 20, 1997A method of determining a restoration route as in a fully or partially meshed communications network of nodes, comprising setting, at a slave end node for an existing route, a timeout for receiving a number of forward route-finder signatures from which it will select the signature representing the potential restoration route having the shortest length and return a route confirmation signature; switching, to act as master end node for the existing route and send reverse route-finder signatures to its neighbouring nodes; switching, upon receipt of a reverse route-finder signature at a master end node for an existing route, to act as slave end node, and send a corresponding return signature. Where a slave end node receives a backtrack signature indicating that the potential restoration route no longer has sufficient capacity, the node will switch to act as master end node. Where a forward route-finder signature is received after a node has sent a reverse route-finder signature, a priority route confirmation signature is sent. Where a node has sent a forward route-finder signature, received a reverse route-finder signature, sent a confirmation signature, and subsequently receives a priority confirmation signature, then unless a backtrack signature is received two restoration routes will be established and the nodes will select the better one.