Resources Sharing and Fault Tolerance in Distributed Systems

Abstract

This thesis deals with the problem of K-mutual exclusion that can be seen as a generalization of the problem of simple mutual exclusion in distributed ystems and mobile ad hoc networks.Our work is divided into three parts, one eoretical part and two practical parts.In the first part, we first introduce the basic concepts of distributed systems and explain the problem of mutual exclusion and K-mutual exclusion, while showing how these problems have been solved. We also present the notion of dependability, and the fault tolerance methods used to ensure it. In the second part, we propose a new solution to solve the problem of K-mutual exclusion; we explain its operating principle and the new logical structure used. Our solution is based on the use of tokens, and allows ensuring K-mutual exclusion with a reduced number of exchanged messages. This new solution will then be improved by a fault tolerance mechanism that allows the system to continue to operate even in the presence of faults. In the third part of this thesis, we present a new solution to the problems of K-mutual exclusion in mobile ad hoc networks, which exploits routing protocols to ensure resource sharing. This algorithm will also be improved by a powerful fault tolerance protocol.Future perspectives and improvements are proposed at the end to refine these new solutions.