A Novel Location-Free Greedy Forward Algorithm for Wireless Sensor Networks

In this work, we propose a new Greedy Forward algorithm to be used in Wireless Sensor Networks (WSNs) routing protocols. Differently from current Greedy Forward algorithms, which depend on the position information of nodes, our approach uses only the Received Signal Strength Indicator (RSSI) of exchanged packets. Since nodes´ position are usually computed based on three or more distance estimations (commonly by means of RSSI measurements) and the positions of beacon nodes (which have inaccuracies by themselves), by using only RSSI measurements, we should achieve better results. Based on this observation, we propose the RSSR (Received Signal Strength Routing) algorithm with two variants: RSSR Election and RSSR Selection. In the RSSR Election, the next hop is dynamically elected at each step and no packets are required for the routing task. In the RSSR Selection, neighbors exchange packets with RSSI information and the next hop of the packet is then selected from a routing table at each step. Our results indicate clearly that the proposed algorithms have all the benefits of a Greedy Forward algorithm but with better performance and without requiring positions information.