Redundancy and distributed caching in mobile DTNs

Abstract

Delay tolerant networking (DTN) allows endpoints to exchange information in networks where end-to-end path may not exist at any given time. In this opportunistic model, routing and forwarding functionality in intermediate nodes enables data transfer following the store, carry, and forward paradigm. Thereby, even in sparsely populated settings, node-to-node contacts can be exploited for communications where network infrastructure does not exist or is not viable to use. Beyond plain message forwarding, the increasing amount of storage in modern devices enables nodes to hold messages for an extended period of time. This feature can then be utilized to create an opportunistic cooperative storage. Having established how to leverage DTN routing nodes for distributed content retrieval, caching, and storage in previous work, in this paper, we investigate applying redundancy schemes to improve message delivery and content retrieval.