Method, system and node to implement the subnetwork connection protection in a multi-protocol label switching network.

摘要

A method for implementing protection subnetwork connection, SNCP, in a Multi-Protocol Label Switching, MPLS, network wherein the MPLS network nests a subnetwork and a source node of the network MPLS sends a packet operation, administration and maintenance, OAM; the source node is part of the MPLS network without being part of the subnetwork, the subnetwork having a working path and a protection path, the method comprising: copying, by a first node of the subnetwork, the OAM packet received from the node source of the MPLS network and modifying a value of lifetime "TTL" field of the OAM packet to generate an OAM packet of the working path of the subnetwork, referred to hereinafter package "OAMW" and an OAM packet protection path of the subnetwork, called in the following package "OAMp" whose TTL value in the field of OAMW package is equal to the number of hops of the working path and the TTL value in the field of OAMp package equal to the number of hops of the protection path, and the value of TTL field of the OAM packet is set equal to or greater than the maximum number of hops of the MPLS network via the working path and the protection path of subnet; sending, by the first node of the subnetwork, the OAM packet and the OAM W packet for the working path and send the OAM packet and package OAMp the protection path of the subnetwork; distinguishing, by a second node of the subnetwork, the OAMw packet and the OAM packet according to the TTL value in the field of the OAMw packet and the TTL value in the field of the OAM packet, and distinguishing the OAMp packet and the OAM packet according with the value of TTL field OAMp packet and the TTL value field of the OAM packet; and determining, by a second node of the subnetwork, working status of the working path and the protection path of the subnetwork according to the OAMw packet on the working path and the OAMp packet on the protection path, select traffic is received from one of between the working path and the protection path of the subnetwork according to the working state, and transmit the OAM packet transparently.