Performance analysis of slotted rings with finite buffers

Many modelling studies have been conducted on a slotted ring with station buffers which are assumed to be either one or infinity. In reality, stations have finite buffers and arriving packets are rejected at a full buffer. The paper studies the behaviour of a slotted ring with finite buffering capability using a two-dimensional discrete time Markov chain. The characteristics of the single station and its interactions with the other stations in the ring are modelled and superposed on an N-station ring. From the model, it is relatively easy to compute the properties of the ring such as normalised throughput, mean packet access delay and packet rejection probability. The analytical model is validated via simulations. In addition, an infinite buffer model is constructed and compared with the finite buffer model. Using these two models, an optimum buffer length can be computed.