Token ring network

Abstract

A token ring local area network includes workstations running both conventional data and multimedia applications. The latter, which generally requires a minimum throughput in order to be viable, can be split into two further categories; those which cannot tolerate excessive latency (end to end delay), typically interactive applications such as voice communications, and those which are less sensitive to latenoy, typically playback operations, the network recognises three priority levels: (1) for latency-sensitive multimedia applications, (2) for latency-insensitive multimedia applications, and (3) conventional applications. All multimedia applications prior to commencement of any communications over the LAN must request an allocation of throughput from a LAN segment resource manager (LSRM), which will only be awarded if there is currently sufficient available throughput on the LAN to support the attended communication. Furthermore, first priority level applications are also given a maximum token holding time, thereby ensuring rapid circulation of the token, and controlling latency.