Patent ID: 6717953
Filing Date: 2004-04-06
Classification: H04J,Y10S

Abstract:
A method of converting a first synchronous communications signal of a first synchronous digital communication system (SONET) to a second synchronous communications signal for a second communication system (SDH),wherein the first and second communications signals are framed multiplex signals which are composed of multiplex units (TU-2, TU-3, AU-3, AU-4) according to a respective specified multiplex hierarchy in such a way that smaller multiplex units (TU-2, TU-3) are multiplexed in larger multiplex units (AU-4, AU-3) and that the larger multiplex units (AU-4, AU-3) are transmitted in frames (STM-1), wherein the multiplex hierarchy of the first communication system (SONET) comprises at least one level corresponding to a level of the multiplex hierarchy of the second communication system (SDH), whose multiplex hierarchy includes an additional level VC-4) in comparison with the multiplex hierarchy of the first communication system (SONET), and wherein the multiplex units (AU-3) of the first communications signal are converted to corresponding multiplex units (TU-3) of the second communications signal, which are then multiplexed into multiplex units (AU-4) of the additional hierarchy level, characterized in that monitoring functions according to the multiplex hierarchy of the second communication system (SDH) are applied to both communications signals, and that in applying the monitoring functions to the first communications signal, the additional level of the multiplex hierarchy of the second communication system (SDH) is simulated by setting parameters to be monitored to default values.