A Caching Model for Real-Time Databases in Mobile Ad-Hoc Networks

Although caching has been shown to be an efficient technique to improve the performance of database systems, it also introduces the overhead and complexity in maintaining data consistency between the primary copies on servers and the cached copies on clients. Little research has been performed for data caching in the mobile ad-hoc network (MANET) environment where both servers and clients are nomadic. In this paper, a caching model called GMANET is designed to maintain both strong and weak cache consistency for distributed real-time database transaction systems in group-based MANETs, and at the same time, to incur as few update control messages as possible. GMANET is compared with the existing caching models by means of simulation. The experiment results show that the GMANET has the best performance in terms of percentage of transactions processed before their deadlines and is compatible with other caching models in terms of mobile hosts’ energy consumption.