Although mobility management within a network of wireless sensors is a relatively new subject, we envision that a mobile sensor will move through different networks. However, it is very likely that the routing protocol supported in a visited network is different from the one supported by the mobile sensor. In a convergecast communication model, it would suffice for mobile sensors to broadcast its messages into the visited network to have them forwarded to the sink. Though, this can lead to duplication of messages and therefore increase the network traffic in the visited network. In this article, we propose Mobinet whose objective is to enable mobile sensors to detect surrounding sensors in the visited network through passive listening in order to select one of them to transmit messages. We particularly focus on the energy consumption of the mobile sensors and consequently introduce various listening processes to limit the extra energy consumption resulting from the detection of surrounding sensors. Mobinet has been evaluated by simulation. Simulation results show the benefits of Mobinet in terms of message delivery and a lower energy consumption through the listening processes. They also highlight guidelines for future research.

In this paper, we briefly describe an interactive roulette game enabled over a wireless sensor network platform. It basically consists in a train speeding in one way (the spinning roulette) and in a message hopping along some deployed sensors in the other way (the wheeling ball). This demonstration aims at illustrating in an interactive manner the high radio channel randomness in dense wireless sensor networks, as well as its impact on the communication protocols.