DPCA: Data Prioritization and Capacity Assignment in Wireless Sensor Networks

Scheduling different types of data packets, such as high or low priority data packets at the sender node, is important for reducing energy and capacity consumptions and end-to-end delay. Current scheduling schemes of wireless sensor networks use preemptive and non-preemptive scheduling algorithms, which incur relatively long end-to-end transmission delay and high processing overhead. Besides, they do not consider the path capacity, which represents the capacity of the network for transferring as much as sensory data to the sink node(s). Consequently, sensory data are routed to the sink node(s), whatever they are more or less, important for supporting domain applications. To remedy this issue, we propose a method, which differentiates between high and low priority when routing sensory data to the sink node(s). Specifically, the priority of sensory data is determined through a novel capacity assignment mechanism. When the network capacity, which depends on the capacity of routing paths, may not be sufficient for supporting the sensory data routing requirement, sensory data with a relatively high priority should be routed to the sink node(s), while that with a relatively low priority may be decreased or prohibited. Experimental evaluation has been conducted, and the result shows that congestion and packets dropping are reduced, when sensory data can be differentiated in their priority and the network traffic is relatively heavy.