Date Added: Aug 2011
An important but relatively less studied class of network layer protocol for sensor networks is geocast. It allows a sensor node to send messages to all nodes in a given geographical area without the sender node having any knowledge about which nodes are present in that area. Developing a robust geocast protocol for practical sensor networks poses several challenges. Geocast messages should be reliably delivered to the destination area in the presence of unreliable wireless links, a typical characteristic of practical sensor network deployments. The protocol should minimize the number of radio transmissions and avoid control traffic to save energy, which is a scarce resource in sensor networks.