The Multidriver: a reliable multicast service using the Xpress transfer protocol

A reliable multicast facility extends traditional point-to-point virtual circuit reliability to oneto-many communication. Such services can provide more efficient use of network resources, a powerful distributed name binding capability, and reduced latency in multidestination message delivery. These benefits wiU be especially valuable in real-time environments where reliable multicast can enable new applications and increase the availability and the reliability of data and services. In this paper we present a unique multicast service that exploits features in the next-generation, real-time transfer _ layer protocol, the Xpress Transfer Protocol (XTP). In its reliable mode_, the service offers error, flow, and mte-controUed multidestination delivery of arbitrary-sized messages, with provision for the coordination of reliable reverse channels. Performance measurements on a single-segment Proteon ProNET-4 4 Mbps 802.5 token ring with heterogeneous nodes are discussed. ' The transfer layer incorporates the functionalities of the transport and network layers of the ISO OSI Reference Model into a single layer.