Domination and Its Applications in Ad Hoc Wireless Networks with Unidirectional Links

We consider an efficient distributed algorithm for determining a dominating and absorbant set of vertices (mobile hosts) in a given directed graph that represents an ad hoc wireless network with unidirectional links. This approach is based on the concept of dominating set in graph theory. A host v is called a dominating neighbor (absorbant neighbor) of another host u if there is a directed edge (v; u) ((u; v)). A subset of vertices is dominating and absorbant if every vertex not in the subset has one dominating neighbor and one absorbant neighbor in the subset. A quick formation process of a dominating and absorbant set is given and this set can be easily updated when the network topology changes dynamically. Ideas for dominating-set-based routing in an ad hoc wireless network with unidirectional links are also given. The effectiveness of the approach is confirmed through a simulation study.