Termination Detection of Local Computations

Contrary to the sequential world, the processes involved in a distributed system do not necessarily know when a computation is globally finished. This paper investigates the problem of the detection of the termination of local computations. We define four types of termination detection: no detection, detection of the local termination, detection by a distributed observer, detection of the global termination. We give a complete characterisation (except in the local termination detection case where a partial one is given) for each of this termination detection and show that they define a strict hierarchy. These results emphasise the difference between computability of a distributed task and termination detection. Furthermore, these characterisations encompass all standard criteria that are usually formulated : topological restriction (tree, rings, or triangulated networks ...), topological knowledge (size, diameter ...), and local knowledge to distinguish nodes (identities, sense of dire...

• Type: Journal
• Year: 2010
• Where: CORR
• Authors: Emmanuel Godard, Yves Métivier, Gerard Tel
• Keywords: CORR 2010, Detection, Education, Local Computations, Termination Detection