We propose and evaluate a mobile, peer-to-peer Information Retrieval system. Such a system can, for example, support medical care in a disaster by allowing access to a large collections of medical literature. In our system, documents in a collection are replicated in an overlapping manner at mobile peers. This provides resilience in the face of node failures, malicious attacks, and network partitions. We show that our design manages the randomness of node mobility. Although nodes contact only direct neighbors (who change frequently) and do not use any ad hoc routing, the system maintains good IR performance. This makes our design applicable to mobility situations where routing partitions are common. Our evaluation shows that our scheme provides significant savings in network costs, and increased access to information over ad-hoc routing-based approaches; nodes in our system require only a modest amount of additional storage on average.
Katrina M. Hanna, Brian Neil Levine, R. Manmatha