FAPP: A new fairness algorithm for priority process mutual exclusion in distributed systems

In this work, we have proposed a new token based Fairness Algorithm for Priority Processes (FAPP) that addresses both the issues and keeps the control message traffic reasonably low. One major limitation of the token based mutual exclusion algorithms for distributed environment like Raymond's well-known work on inverted-tree topology lies in the lack of fairness. Another aspect of the problem is in handling the prioritized processes. In one of our earlier works, both fairness and priority have been addressed in proposing an algorithm MRA-P. However, MRA-P suffered from some major shortcomings like lack of liveness, high message complexity, etc. The proposed FAPP algorithm, in spite of considering priority of processes, ensures liveness in terms of token requests from low priority processes. Formal verification on FAPP justify properties like correctness of the algorithm, low message complexity, and fairness in token allocation. © 2010 ACADEMY PUBLISHER.