Proactive neighbor localization based on distributed geographic table

A large set of valuable applications, ranging from social networking to ambient intelligence, may see their effectiveness and appeal improved when supported by the large‐scale, real‐time tracking of mobile devices, either carried by humans or embedded into vehicles. A centralized approach, where few servers would collect position data and provide them to interested consumers, would hardly cope with the resource demand of the foreseen huge increase of users interested in location‐based services and with the flexibility needs of emerging user‐generated services. The purpose of this paper is to propose a decentralized peer‐to‐peer approach to cope with these requirements, for which positioning information flows directly among mobile devices incurring in limited data exchange.

The authors propose a decentralized peer‐to‐peer approach for which positioning information flows directly among mobile devices incurring limited data exchange. A peer‐to‐peer overlay scheme is introduced called distributed geographic table (DGT), where each participant can effectively retrieve node or resource information (data or service) located near any chosen geographic position. Next, the authors describe a DGT‐based localization protocol that allows each peer to proactively discover and track all peers that are geographically near to itself.

The authors provide a performance analysis of the protocol by simulating several 1,000 users that move across an urban area according to realistic mobility models. The results show that the solution is effective, robust, scalable and highly adaptable to different application scenarios.

The new contributions of this paper are a general framework called DGT, which defines a peer‐to‐peer strategy for mobile node localization, and a particular instance of the DGT that supports applications in which every node requires to be constantly updated about the location of its neighbors.