Primary copy method and its modifications for database replication in distributed mobile computing environment

摘要

Rapidly expanding cellular communication technology, wireless LANs and satellite services have made it possible for mobile users to access information anywhere and at any time. In a mobile computing environment replication might be considered as an essential technique providing reliability, throughput increase and data availability. This paper addresses the replica control protocols with an emphasis on workstation mobility issues. The modifications that have to be made to the primary copy method for replicated database management strategies in order to address the effect of mobility on the existing replica control protocols are analysed and proposed. A variation of the primary copy algorithm, called virtual primary copy method is proposed and it is shown that this method is well suited for the distributed mobile computing environment. The performance of virtual primary copy method comparative to traditional primary copy method using computer simulation is analysed.