Abstract
Sensor networks are meant for sensing and disseminating information about the environment they sense. The criticality of a sensed phenomenon determines it’s importance to the end user. Hence data dissemination in a sensor network should be information-aware. Such information-awareness is essential firstly to disseminate critical information more reliably and secondly to consume network resources proportional to criticality of information. In this paper, we describe a protocol called ReInForM to support information awareness in sensor networks. Using ReInForM, data can be delivered at desired levels of reliability at proportional cost, in spite of the presence of significant channel errors. It uses the concept of dynamic packet state in context of sensor networks to control the number of paths required for the desired reliability using only local knowledge of channel error rates and does not require any prior computation or maintenance of these multiple paths. We also show that for uniform unit disk graphs, multiple edge-disjoint paths numbering as many as the average node degree, exist between any source and sink with very high probability. These paths exist in a thin band between source and sink having low deviation from the optimal path. ReInForm utilizes this property in its randomized forwarding mechanism which results in use of all possible paths in this band. Thus as a side effect ReInForM leads to load balancing as well.