Connectivity fault management in a communication network

Abstract

Methods and apparatus are disclosed for monitoring a Maintenance Association (MA) for Connectivity Fault Management (CFM) in a network supporting Equal Cost Multiple Paths (ECMP). A set of ECMP paths is generated for sending data between endpoints in the network. Furthermore, a set of ECMP MAs is created that are used for monitoring the generated ECMP paths between the endpoints. The created set of ECMP MAs is subsequently used for sending monitoring packets. ECMP path MAs therefore conform to existing CFM operation and are compatible with both ECMP point to point path MAs and ECMP multipoint path MAs.

What is claimed is: 
     
         1 . A method of monitoring a Maintenance Association for Connectivity Fault Management in a network supporting Equal Cost Multiple Paths, ECMP, the method comprising:
 generating a set of ECMP paths for sending data between endpoints in the network;   creating a set of ECMP Maintenance Associations for monitoring the generated ECMP paths between the endpoints; and   using the created set of ECMP Maintenance Associations for sending monitoring packets.   
     
     
         2 . The method according to  claim 1 , wherein each monitoring packet comprises a Connectivity Fault Management Protocol Data Unit. 
     
     
         3 . The method according to  claim 1 , further comprising generating the set of ECMP paths using ECMP Point to Point paths, each of the ECMP Point to Point paths comprising a set of equal shortest length connectivity paths between two endpoints of the ECMP Point to Point path. 
     
     
         4 . The method according to  claim 1 , further comprising generating the set of ECMP paths using ECMP multipoint paths, the multipoint paths comprising a set of connectivity multipoint paths among the same endpoints. 
     
     
         5 . The method according to  claim 4 , wherein each ECMP path comprises an ECMP multipoint path having N endpoints, the method further comprising identifying each ECMP multipoint path using a Group address. 
     
     
         6 . The method according to  claim 4 , further comprising identifying each ECMP multipoint path associated with the N endpoints using a Group MAC address. 
     
     
         7 . The method according to  claim 6 , further comprising constructing the Group MAC address by applying an operation on Backbone Service Identifier values associated with the ECMP multipoint paths. 
     
     
         8 . The method according to  claim 1 , further comprising monitoring an ECMP path by sending the monitored packet using an identifier associated with the monitored ECMP path. 
     
     
         9 . The method according to  claim 8  wherein the identifier is selected from any of a Flow Hash and a Group MAC address identifying the path. 
     
     
         10 . The method according to  claim 1 , further comprising monitoring a plurality of ECMP paths by sending monitored packets in groups cyclically on each monitored ECMP path, using an identifier associated with each monitored ECM P path. 
     
     
         11 . A node for use in a communications network supporting ECMP, the node comprising:
 a processor for generating a set of ECMP path MAs for sending data between endpoints;   the processor being further arranged to create a set of ECMP Maintenance Associations for monitoring the generated ECMP paths between the endpoints; and   a transmitter for sending monitoring packets using the set of generated ECMP paths.   
     
     
         12 . The node according to  claim 11 , further comprising a computer readable medium in the form of a memory for storing information mapping at least one Service Identifier to each generated ECMP path. 
     
     
         13 . The node according to  claim 11 , wherein the processor is further arranged to generate the monitoring packets using ECMP Point to Point paths, each of the ECMP Point to Point paths comprising a set of equal shortest length connectivity paths between two endpoints of the ECMP Point to Point path. 
     
     
         14 . The node according to  claim 11 , wherein the processor is further arranged to generate the monitoring packets using ECMP multipoint paths comprising a set of connectivity multipoint paths among a plurality of endpoints. 
     
     
         15 . The node according to  claim 14 , wherein the processor is arranged to identify each ECMP multipoint path monitoring packet using a Group MAC address for each ECMP multipoint path. 
     
     
         16 . The node according to  claim 15  wherein the processor is arranged to construct each Group MAC address by applying an operation on Backbone Service Identifier values associated with the ECMP multipoint paths. 
     
     
         17 . A non-transitory computer readable medium which, when run on a node, causes the node to perform the method of  claim 1 . 
     
     
         18 . A vessel or vehicle comprising the node as claimed in  claim 11 .