Transport Protocol Requirements for Distributed Multimedia Information Systems
Lek Heng Ngoh · The Computer Journal · 1989
Typical Distributed Multimedia Information Systems are made up of clusters of workstations connected by local area networks. Such systems allow users to exchange information in the form of ‘documents’ containing text, graphics and voice; some systems support both store-and-forward and real-time material. Here we consider various transport protocol requirements and conclude that some essential features are not available with existing protocols. The main objective of the work described here is to investigate the use of transport protocols which support the notion of multicast logical connectivity, both within a single network and in an internet environment. In this paper we show that protocols with multicasting capabilities can yield a substantial performance improvement over protocols which support only unicast logical connectivity. We propose ways in which multicasting can be exploited to suit our application. A prototype implementation of a multicast communication facility based on these requirements is presented, and an application model is used to measure the transport protocol performance under various possible system configurations and loads. Results of performance measurements are presented, based on experiments carried out on an Ethernet-based internet.