Efficient Self-stabilizing Graph Searching in Tree Networks
چکیده
The graph search problem asks for a strategy that enables a minimum sized team of searchers to capture a “fugitive” while it evades and potentially multiplies through a network. It is motivated by the need to eliminate fast spreading viruses and other malicious software agents in computer networks. The current work improves on previous results with a self-stabilizing algorithm that clears an n node tree network using only 1+log n searchers and O(n log n) moves after initialization. Since Θ(log n) searchers are required to clear some tree networks even in the sequential case, this is the best that any self-stabilizing algorithm can do. The algorithm is based on a novel multi-layer traversal of the network.