A Hierarchical Approach to Resource Awareness in DHTs for Mobile Data Management

Data is increasingly distributed across networks of mobile nodes such as wireless sensor networks, distributed smartphone applications, or ad hoc recovery networks in disaster scenarios, but must still be reliably collected, stored, and retrieved. While such networks run in either ad hoc mode or use existing infrastructure, all of them must deal with node heterogeneity. Wireless nodes invariably have differing levels of power availability, and often varying connectivity and computing power. While many distributed hash tables (DHTs) have been designed for mobile ad hoc or heterogeneous networks, they do not consider differences in node strength, or resource availability, for an arbitrary number of resource availability levels. In this paper, we present a scalable, location aware, hierarchical DHT that utilizes nodes’ varying resource availability levels to increase and prolong the mobile network’s data storage and retrieval capabilities. Furthermore, we compare this DHT to other location aware flat and hierarchical approaches, examining their structures’ suitability for nodes with varying resource availability.