UC Santa Barbara

The mobile, wireless, and self-organizing features of ad hoc networks pose many challenges with respect to continuous availability and accessibility of data. In such a dynamic environment, there are many advantages in replicating a data item so there are multiple copies, including reduced response times and higher data availability. Also, if done efficiently, replication can help reduce energy usage. In this paper, we propose the Expanding Ring replication strategy for pull-based information dissemination environments. One of our primary objectives is the development of a lightweight scheme for mobile nodes. We evaluate the performance of our scheme with respect to a number of parameters and compare it to a system without replication. Our results show a reduction in the average response times and the message processing overhead on nodes. The scheme also does well when both, the overall willingness of nodes to cache data and their individual caching capabilities vary.