Approximate Performance Analysis of the DQDB Acess Protocol

Abstract We present an approximate performance study of the DQDB medium access protocol. The aim of the queuing analysis described in this paper is to provide close-form solutions, which should be easy to evaluate but deliver sufficiently accurate performance measures describing major behaviors of the protocol. The analysis is based on a decomposition of the medium access delay, using the technique of embedded models. The non-isochronous station-to-station traffic matrix, which consists of traffic streams assumed as Poisson, can be chosen arbitrarily. A percentage of preassigned isochronous traffic in the system is taken into account. It is shown by comparison with simulation results that the approximation technique developed in this paper is appropriate for a wide range of protocol parameters. The efficient analysis method also shows various protocol properties, which have been partly discovered in the literature by means of simulations.