Evolution and integration of a multi-media communications network

A possible scenario is considered for the evolution of the public switched network to serve the communication needs of multimedia terminals. The authors explain how the local-area network (LAN) is evolving toward the metropolitan-area network (MAN) and the wide-area network (WAN), which can interconnect multiple LANs and high-speed workstations dispersed in different parts of a metropolitan area. They then describe the evolution of the ISDN provide high-speed communication services such as video, and in addition, the evolution of the X.25 packet network toward the frame-relaying network. Such a network improves the throughput/delay performance of the data network. It is concluded that these different evolutionary paths should eventually converge to the next generation switching system that will provide integrated voice/data/image/video capabilities