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.Friedemann Matternreceived the Diploma in computer science from the University of Bonn, West Germany, in 1983.He is now a research scientist in the Department of Computer Science at the University of Kaiserslautern and is currently completing his Ph.D. His primary research interests include distributed algorithms, programming language design, and compiler construction. The author can be reached by electronic mail via mattern @ incas.uucp or mattern % uklirb.uucp @ Germany.csne.This work has been supported by the Deutsche Forschungsgemeinschaft (DFG) as part of the SFB124 research project VLSI-Design and Parallelism