Recent advances in networking technology has enabled new multimedia and process control applications. These applications require real-time communication services with stringent performance guarantees expressed in terms of delay, delay jitter, throughput and loss rate. Current network architectures and protocols are designed to support best-effort services and they are inefficient in supporting real-time services.

In this paper, we survey real-time communication architectures and protocols both in packet-switching networks and in multiple-access networks. For each network a service model is presented as a general framework. Specifically, the service model for a packet-switching network is composed of a specification for traffic characterization and performance requirements, a routing protocol, a resource reservation protocol and a packet service discipline at switching nodes. The model for a multiple-access network, on the other hand, includes a basic traffic characterization and a MAC-layer real-time scheduling algorithm. This paper surveys the recent developments in each component of the service models with comparisons of alternative techniques. (Also cross-referenced as UMIACS-TR-97-04)