ENERGY-EFFICIENT REPLICATION EXTENDED DATABASE STATE MACHINE IN MOBILE AD-HOC NETWORK

A mobile ad-hoc Network (MANET) is a collection of mobile servers and clients that can communicate with each other directly via wireless link in the absence of fixed wired infrastructure. MANET needs to consider specially data replication that is traditionally seen as a way to increase the availability, reliability and performance of transaction processing. The reason why is that additional energy for data broadcasting can be consumed to maintain consistency if the database is fully replicated among all mobile servers. In this paper, we propose an eager replication scheme, named E-DRM (Eager replication extended Database State Machine) for MANET where both server and client have energy restrictions. That is, E-DRM extends database state machine scheme suitable to MANET with taking energy into consideration. According to E-DRM, tentative transactions are processed locally at single small mobile host (SMH) and are forwarded to one of large mobile hosts (LMH)s as soon as broadcast cycle starts. After that, LMHs certify tentative transactions as correct through only one message broadcasting. As a result, the proposed scheme can validate all conflicts in LMHs locally; hence, it can improve the performance by reducing additional energy consumed to maintain consistency and the number of message broadcasting.