EFFICIENT PROTECTION MECHANISMS IN A RING TOPOLOGY NETWORK UTILIZING LABEL SWITCHING PROTOCOLS

摘要

Efficient protection mechanisms for ring based label-switching networks are designed to protect point-to-point label switching paths (LSPs) while preventing misconnection and mismerge situations. The protection switching is performed by nodes adjacent to the point of failure. The switching decision is based on a locally detected signal fail condition. The operation of the protection mechanisms does not require the use of any protection switching protocol. In one embodiment of the present invention, the protection is achieved by assigning an exclusive label to each LSP. In another embodiment, the protection is achieved by providing a closed-loop protection tunnel and assigning a tunnel label for each such protection tunnel. In yet another embodiment, the protection is achieved by establishing a mirror path for each protected LSP.