Quorum structures for fault-tolerant distributed mutual exclsuion

• Main Authors: Jehn-Ruey Jiang, 江振瑞
• Other Authors: Shing-Tsaan Huang
• Format: Others
• Language: en_US
• Published: 1995
• Online Access: http://ndltd.ncl.edu.tw/handle/29426809983095132968

博士 === 國立清華大學 === 資訊科學學系 === 83 === Quorum-based algorithms are an important class of algorithms to achieve distributed mutual exclusion. They are resilient to network partitioning caused by site and/or network link failures and usually evoke low communication cost. The basic idea of them is simple-a site should collect permissions (votes) from all sites of a quorum to enter the critical section. If we can assure that any pair of quorums have a non- empty intersection and each site gives its permission to only one site at a time, mutual exclusion is then guaranteed. The collection of quorums used by a quorum-based algorithm is called a quorum structure. According to different mutual exclusion scenarios, several types of quorum structures have been proposed: coterie, wr-coterie and k-coteries, which are related to distributed mutual exclusion, replicated data consistency and distributed k- mutual exclusion, respectively. In this dissertation, we propose novel methods for constructing coteries, wr-coteries and k-coteries that are nondominated and/ or of constant expected quorum size. The proposed methods can easily be extended to solve the problems of mutual exclusion, replicated data consistency or k-mutual exclusion in a distributed system. Nondominated quorum structures are favorable because they are candidates to achieve the optimal availability, the probability that a quorum can be form in an error-prone environment. On the other hand, quorum structures of constant expected quorum size are preferable because when the proposed methods are applied to solve the problems mentioned, the message cost is directly proportional to the quorum size.