Reliable collaborative decision making in mobile Ad hoc networks

Abstract

Mobile units, such as vehicles in a traffic flow or robots in a factory, may use sensors to interact with their environment and a radio to communicate with other autonomous units in the local area. Collaborative decision making can be carried out through information sharing amongst these units and result in cooperative problem solving. Examples of solutions include coordinated vehicle control for collision avoidance and executing complementary path plans for robots on a factory floor. We propose an application-level protocol that enables units to contribute their local knowledge and actions to a shared global view of the problem space. The protocol uses a time-driven token ring architecture to permit any unit to reliably broadcast a message to the entire group. The protocol ensures that all units commit the same set of received messages in the same order by a deadline, and it upholds these guarantees in the presence of channel failures, hidden units, and a changing set of collaborators. Units in the network are made aware of when others fail to maintain the global view. Failing units may be required to operate autonomously, pending information recovery. © IFIP International Federation for Information Processing 2004.