New communication transfer modes for the broadband ISDN

Broadband integrated-services digital networks (B-ISDNs) represent the evolution of common carrier networks to provide in the metropolitan and the long-distance areas high-speed (multigigabit-per-second) multimedia communication and information services. Both synchronous and asynchronous transfer modes (STMs and ATMs) are included in the evolving B-ISDN scenario for the operation of multiplexing, transmission, and switching equipment throughout the network. The authors briefly describe the challenge of using STM and ATM to implement broadband multimedia applications, including voice, data, high-definition graphics, and full-motion video. Such multimedia service integration is to be offered by the B-ISDN for both the direct access of multimedia user workstations and the interfacing of local user networks dedicated to various applications. The authors predict the progressive availability of (1) STM transmission and cross-connect equipment at 150 and 600 Mb/s and 1.2 and 2.4 Gb/s and (2) ATM access interfaces and switching equipment at 50 and 150 Mb/s, using the solution of ATM embedded into STM frames