On the provisioning of guaranteed QoS in wireless sensor networks through limited service polling models

Data gathering in a timely and reliable fashion has been a key concern in wireless sensor networks particularly related to military applications. The introduction of real time communication has created additional challenges in this area with different communication constraints. Since sensor networks represent a new generation of time-critical applications, it is often necessary for communication to meet real time constraints. However, research dealing with providing QoS guarantees for real time traffic in sensor networks is still immature. To provide guaranteed QoS in WSN, this paper presents a novel analytical model based on limited service polling discipline. The proposed model implements two queues in a sensor node which are being served according to round robin service. The model is based on M/D/l queueing system (a special class of M/G/l queueing systems), which takes into account two different classes of traffic in a sensor node. The exact queueing delay in a sensor node for corresponding classes is calculated. Further, the analytical results are validated through an extensive simulation study.