Priority-based bandwidth allocation in wireless sensor networks

In Wireless Sensor Networks (WSN) a set of motes monitors the environment by measuring some physical phenomena such as humidity, light, temperature, vibrations. The coexistence of different data types arises the problem of assigning the network resources in a fair way by taking into account possible different priorities among the traffic streams. In this paper we propose an allocation control scheme which is easy to implement, meets the limited resources of sensor nodes, and does not require extra control traffic in the WSN. Our scheme is based on the idea that the motes maintain a window with the classes of the latest transmissions. We propose an analytical model and provide an algorithm to study the performance of this allocation scheme with respect to the throughput and the fairness achieved. The model is a continuous time Markov chain which is proved to be dynamically reversible (although not reversible) and admits a product-form equilibrium distribution.