STM signal transfer techniques in ATM networks

Some of the issues of converting synchronous transfer mode (STM) signals into asynchronous transfer mode (ATM) signals and vice versa are considered. During the period when ATM and STM networks coexist, it is necessary to convey STM signals, such as virtual container signals (VC-II, VC-2 and VC-3), with ATM technologies. The STM signal transfer unit, the VC level or TU/AU level, is considered, and the best choice is found to be TU/AU. An algorithm for handling lost or misbelieved cells using the sequence number and its protection is presented. Cell delay variations are estimated using tandem M/D/1 queuing models. Two buffer control methods are considered for smoothing cell delay variations. A key point is to prevent buffer underflow. Two methods for achieving this are proposed