Single-moment analysis of unreliable trunk networks: two methods for the network grade-of-service

Traditionally, research into circuit-switched (C-S) communications networks has been divided into two areas, reliability and performance. The combined performance and reliability measure chosen is the network grade-of-service (NGOS), i.e. the overall probability of blocking, averaged over all node pairs, taking into account both the offered traffic between node pairs and the link (trunk group) availabilities. Two methods are given for the single-moment analysis of C-S networks with reliable nodes but unreliable links. UNRELGOS is based on earlier work. MKV-GOS employs a Markov model for an unreliable link, developed by the author, in combination with the earlier work, so as to greatly reduce execution time, though not without some cost in accuracy.