Patent ID: 6049529
Filing Date: 2000-04-11
Classification: H04J,H04L

Abstract:
In a telecommunications network having a plurality of interconnected nodes and at least one restoration domain defined to include a subset of said interconnected nodes, data streams each including frames of successive groups of multiple data bits traversing through said network, a method of integrating into at least one of said data streams a path verification message as said at least one data stream traverses along a path to verify the integrity of said path within said domain, said path adaptable to extend outside of said domain, said method comprising the steps of:(a) selecting at least one bit in at least one group of said successive groups of bits that repeats in each frame of said one data stream, the value of said one bit being probed at fixed time intervals by the nodes interconnected to effect said path, said at least one data stream passing through equipment along said path;(b) determining the time period separating successive ones of said time intervals whereat the value of said one bit is probed by said nodes;(c) varying the value of said one bit during a predefined portion of each said time period, value changes of said one bit during said predefined portion of each said time period having been determined not to affect the operation of said equipment along said path; and(d) sending frames having said value varied one bit during said predefined portion of said time period along said path, successive ones of said value varied bits of corresponding successive ones of said frames sent during said predefined portion of at least one said time period forming at least one part of said path verification message for confirming the integrity of said path.