Geographic Forwarding in Wireless Sensor Networks with Loose Position-Awareness

Geographic-based routing techniques are promising for wireless sensor networks, which suffer from severe energy constraints and a low throughput nature. In its simplest form, greedy geographic forwarding faces the problem of a low delivery ratio. Other protocols use the right hand rule to guarantee delivery. They nevertheless assume nodes know their exact position, whereas positioning systems offer only limited accuracy. In this paper, we propose to use path-recording mechanisms, where nodes append their identifier to the header of the message, together with geographic forwarding. While yielding a comparable number of hops for a message to reach destination than existing routing protocols with guaranteed delivery, this technique offers guaranteed delivery regardless of the positioning accuracy. This makes path-recording particularly suitable for real-world wireless sensor network implementations.