A family of smallest symmetrical four-states firing squad synchronization protocols for ring arrays
Résumé
An existence or non-existence of five-state firing squad synchronization protocol has been a longstanding and famous open problem for a long time. In this paper, we answer partially to this problem by proposing a family of smallest four-state firing squad synchronization protocols that can synchronize any one-dimensional ring cellular arrays of length n = 2^k for any positive integer k. The number four is the smallest one in the class of synchronization protocols proposed so far.