The First Fully Polynomial Stabilizing Algorithm for BFS Tree Construction

International audienceThe construction of a spanning tree is a fundamental task in distributed systems which allows to resolve other tasks (i.e., routing, mutual exclusion, network reset). In this paper, we are interested in the problem of constructing a Breadth First Search (BFS) tree. Stabilization is a versatile technique which ensures that the system recovers a correct behavior from an arbitrary global state resulting from transient faults.A fully polynomial algorithm has a round complexity in $O(d^a)$ and a step complexity in $O(n^b)$ where $d$ and $n$ are the diameter and the number of nodes of the network and $a$ and $b$ are constants. We present the first fully polynomial stabilizing algorithm constructing a BFS tree under a distributed daemon. Moreover, as far as we know, it is also the first fully polynomial stabilizing algorithm for spanning tree construction. Its round complexity is in $\Theta(d^2)$ and its step complexity is in $O(n^6)$