Data dissemination and gathering in sensor networks

Sensor networks [1] contain a large number of sensor nodes that collect some kind of data, for example temperature or air pressure, from the environment. Even though both wireless ad hoc networks and sensors networks communicate wirelessly, they are quite different from each other. The number of nodes in sensor networks can be several orders of magnitude larger than in ad hoc networks. Sensor nodes are usually quite small, and they have very limited battery power. Their batteries are often not replaceable or rechargeable. Finally, sensor nodes may lack an unique identifier like an IP address that is always present in ad hoc networks.