Message delay analysis of the DQDB (IEEE 802.6) network

The analytical evaluation of the message delay in a distributed queue dual bus (DQDB) network is investigated. The authors extend the results obtained by C. Bisdikian et al. (1990), which assumes that each network station can queue at most one packet, to the case of station queues each holding an entire message containing l packets. An expression is obtained for the number of requests queued ahead of an arriving message. Given this expression, the average message delay can be calculated. One conclusion drawn from the analysis is that the average steady-state message delay is linear in sufficiently large l. It is also concluded that the message delay increases considerably with the network load. The analytical results predict the position-dependent characteristics of stations in a heavily loaded network and explain some observations and results of earlier simulation studies.<<ETX>>