Multi-version timestamp certification for disconnection protocol in mobile computing

Abstract

Wireless technology inspires many new thoughts to the traditional distributed database systems. "Disconnection" is a standard operation of the mobile computing which the traditional distributed systems usually treat as a failure. A mobile unit informs the fixed servers prior to disconnection. During the time of disconnection, the mobile unit operates by itself with no network support. Upon reconnection, the fixed servers should be able to synchronize the updates and commit the transactions made by the mobile unit during the disconnecting period. Allowing the disconnected mobile units to operate alone may generate some conflicts upon reconnection. This thesis presents the Multi-Version Timestamp Certification for Disconnection Protocol in Mobile Computing to resolve the data inconsistency called by the disconnection protocol. The objectives of this new protocol includes: (1) to solve data consistency problem between the distributed static servers and moving mobile units and (2) to maximize transaction concurrency for transactions.