Packet-Switching Network Performance Under Real-Time Voice-Call Loading

Abstract The performance characteristics of packet-switching networks carrying real-time voice calls are of major interest in network design. This paper describes a real-time voice-call model in which voice packets are transmitted over virtual circuits on a variety of simulated packet-switching networks. These networks range from current mid-range packet-switching networks to those using frame relay with T1 links and cell relay with fiber-optic links. Performance characteristics under varying voice-call loads are presented. These characteristics include node utilization statistics, circuit utilization statistics, nodal buffer use, buffer use by circuits, packet queue time, packet-switch wait time, mean end-to-end packet delay, and voice delays.