Priority-based service differentiation scheme for IEEE 802.15.4 sensor networks

In sensor networks, data packets transmitted by different devices in home networking and industrial applications maintain different levels of importance. In this paper, we propose two mechanisms for IEEE 802.15.4 sensor networks to provide multi-level differentiated services which are required by each and every device. Mathematical model based on the discrete-time Markov chain is presented and is analyzed to measure the performance of the proposed mechanisms. Numerical results show the effects of the variation of contention window size and backoff exponent for service differentiation on 802.15.4 sensor networks. From the results, we derive that contention window size is more affective than backoff exponent on the saturation throughput while backoff exponent is more affective than contention window size on the average delay of every device. Simulation results are given to verify the accuracy of the numerical model. (c) 2006 Elsevier GmbH. All rights reserved.