Maintaining Data Consistency Using Timestamp Ordering in Real-Time Broadcast Environments

The broadcast-based data dissemination in wireless environments poses new challenging issues on data consistency of transaction processing. In this paper, we first adapt the optimistic concurrency control with forward validation to the broadcast environments. The adapted protocol gives autonomy between the mobile clients and the server such that the mobile clients can read consistent data off the air without contacting the server. However, it suffers from excessive transaction restart that affects the timeliness of mobile transactions. Therefore, we propose a new protocol based on timestamp ordering that can show significant performance improvement. The timestamp ordering technique enjoys a number of benefits from flexible adjustment of serialization order by exploiting the semantics of readonly transactions, which comprise most of the existing applications. The simulation results confirmed that the proposed protocol could be an efficient and effective approach to transaction processing in real-time broadcast environments for meeting transaction deadlines.