Service Differentiation based on Contention Window with Enhanced Collision Resolution LR-WPANs

The IEEE 802.15.4 MAC [1] standard defines the channel access for low-rate, low-power communication applications such as Wireless Sensor Networks but does not differentiate between high or low priority data. We study few priority based service differentiation mechanisms which distinguish between such data for each and every device, and also let high priority have better channel access as compared to low priority. We also study a mechanism, which improves collision resolution in CSMA algorithms for 802.15.4. In this paper, we propose a service differentiation mechanism for IEEE 802.15.4 based on varying Contention Window parameter and enhance collision resolution. Our proposed algorithm not only deliver service differentiation according to class priority, but also adapts to the backoff exponent according to the channel contention information collected during CCA. Keywords— IEEE 802.15.4, Service Differentiation, Contention Window, Enhanced Collision Resolution, LR-WPAN.