An autonomous energy-aware routing scheme: a supplementary routing approach for path-preserving wireless sensor networks

One of the hottest research topics is how to reduce energy consumption to prolong the lifetime of a WSN. Some nodes of a WSN may be isolated from others, particularly when all their neighbors have crashed or run out of energy, and are thus no longer helpful in collecting and relaying messages, even though their batteries still retain some level of energy. To avoid this, in this paper, we propose a supplementary routing approach, named Energy-aware routing (EnAR in short), which can help to extend the lifetime of a WSN by integrating itself with the routing scheme of the host WSN. With the EnAR, a node in a given WSN (denoted by host WSN) checks the amount of its remaining energy, each time the node receives a request, to see whether it should reject or accept the request. The WSN routes messages through other communication paths when nodes on the original path have consumed too much energy under the condition that alternate paths truly exist. One of the alternate paths will be chosen to relay messages to prevent nodes along the original path from exhausting all their energy so that the WSN can last longer. Our experimental results show that this scheme is applicable to and suitable for an environment with decentralized control, and is able to effectively prolong the lifetime of a WSN.