Analysis of the IEEE 802.4 token-passing mechanism with noise

The IEEE 802.4 token-passing bus had been widely accepted as the standard for factory local-area networks. In this paper, the token-passing mechanism of the IEEE 802.4 under noisy environment, which is an usual case when applied to fields, is analyzed. The interference of noises in ring maintenance time can result in wrong operations, such as loss of the token, failure to pass the token, etc. It is assumed that noises occur in groups as noise clusters with Poisson arrival distribution and exponential length distribution. The mean token-passing time and the mean token rotation time of noisy network is derived analytically