Conceptual issues for ATM

The authors discuss the asynchronous transfer mode (ATM), which has been strongly promoted as the transport structure for future broadband telecommunication networks by CCITT Study Group XVIII (internationally) and TISI (North America). ATM is a transport technique based on fast packet switching, where the information is packed into fixed-size cells of relatively short length. The authors do not question the technical feasibility of ATM at 150 Mb/s rates, but they maintain that the state of system definition is such that ATM cannot be unequivocally supported as a concept. Furthermore, they feel that there is danger in premature standardization of system parameters while the system concept itself is still in flux. They identify four major areas where the system concept needs to be clarified before standardization can proceed: grade of service, accounting, compatibility, and scaling