A fault-tolerant triangular mesh protocol for distributed mutual exclusion

In the problem of mutual exclusion, concurrent access to a shared resource using a structural program abstraction called a critical section (CS) must be synchronized such that at any time only one process can enter the CS. In the paper, we propose a triangular mesh protocol for mutual exclusion, in which the nodes in the system are organized into a triangular mesh and the quorum size is k that is O(/spl radic/N), where N is the number of nodes in the system and is equal to k(k+1)/2. The protocol is fault-tolerant up to (k-2) site failures and communication failures in the worst case, even when such failures lead to network partitioning. From our simulation study, the proposed protocol can have higher availability than S.Y. Cheung et al.'s grid protocol (1992). Moreover, the quorum size of the proposed protocol will be less than that in A. Kumar's HQC protocol (1991) when N is greater than or equal to 15, and can be less than that in Agrawal et al.'s tree quorum protocol when node failures occur.