What is Localized Routing

Routing is the process of finding a path from a source node to a destination node. Since each node has a limited transmission range, the message is normally forwarded by other nodes in an ad hoc or sensor network. Therefore routes normally consist of several hops. Proposed routing schemes can be divided into topological and position based, depending on the availability of geographic location for nodes. Topological routing may be proactive or reactive. Position based routing consists of greedy approaches applied when a neighbor closer to the destination (than the node currently holding the packet) exists, and recovery schemes otherwise. In order to preserve bandwidth and power which are critical resources in ad hoc and sensor networks, localized approaches are proposed, where each node acts based solely on the location of itself, its neighbors, and the destination. There are various measures of optimality which lead to various schemes which optimize hop count, power, network lifetime, delay, or other metrics. A uniform solution based on ratio of cost and progress is described here