ALGORITHMS FOR DISTRIBUTED TERMINATION DETECTION

The termination problem for distributed computations is analyzed in the general context of asynchronous communication. In the underlying computational model it is assumed that messages take an arbitrary but finite time and do not necessarily obey the FIFO rule. Time diagrams are used as a graphic means of representing the overall communication scheme, giving a clear insight into the difficulties involved (e. g. , lack of global state or time, inconsistent time cuts) and suggesting possible solutions. Several efficient algorithms for the solution of the termination problem are presented. They are all based on the idea of message counting but have a number of different characteristics. The methods are discussed and compared with other known solutions.