ISO 8802/5 token ring local-area networks

Abstract

Token ring networks are the second most commonly used type of local-area network (LAN). The second version of the formal token ring multiple access mechanism, ISO 8802/5, was released in late 1995 and this rationalised many of the new developments, e.g. the 16 Mbit/s solutions. The latest innovations are the full duplex dedicated token ring and the development of a 100 Mbit/s high-speed token ring solution. To many people's surprise there is an extensive legacy of token ring installations and the latest innovations, such as token ring switching, are an attempt to maintain and support this significant market presence. Token ring is designed to provide high throughput under heavy loads (something which is normally impossible for Ethernet to sustain) but in most cases it is used in typical office environments where there is infrequent occurrence of heavy loads.