Distributed computation of a spanning tree in a dynamic graph by mobile agents

We describe a distributed algorithm for computing spanning trees in dynamic networks by using mobile agents. Each agent uses a random walk to move in the network and to construct a spanning subtree for the nodes visited for the first time. Spanning subtrees are merged when agents enter in an already discovered area of the network. In this case, we clone the agent having higher color to capture and to annex the adjacent subtree. We discuss in this paper this operation of agent cloning and show that it is useful to construct an efficient distributed algorithm for computing a spanning tree. The correction and the termination detection are also investigated. We give an implementation and a few experimental results which show the practical efficiency of the method.