1 Introduction
Multi-sensor networks (MSN) are being deployed in a wide variety of application areas ranging from military sensing to environmental monitoring and traffic control. Suchnetworks consist of a number of sensors connected via a communication network. Each sensor is able to sense their local environment, but can also make use of data transmitted from neighbouring sensors in order to improve the accuracy of their own measurements (e.g. by combining their own noisy observation, with the observations from a number of other sensors, in order to reduce the final uncertainty).