Economic incentive-based brokerage schemes for improving data availability in mobile-P2P networks

In mobile ad hoc peer-to-peer (M-P2P) networks, data availability is typically low due to rampant free-riding, frequent network partitioning and mobile resource constraints. This work proposes the E-Broker system for improving data availability in M-P2P networks. The main contributions of E-Broker are threefold. First, it proposes the EIB (Economic Incentive-based Brokerage) scheme, which incentivizes relay peers to act as information brokers for performing value-added routing and replication in M-P2P networks , thereby effectively improving data availability. Second, it proposes the EIB+ (enhanced Economic Incentive-based Brokerage) scheme, which extends the EIB scheme by incorporating three different broker scoring strategies for providing additional incentives to brokers towards providing better service. Moreover, EIB+ facilitates load-sharing among the peers. Third, it experimentally determines the number of brokers, beyond which the mobile peers are better off without a broker-based architecture i.e., they can directly access data from the data-providing peers. Our performance evaluation indicates that the proposed schemes are indeed effective in improving query response times, data availability and query hop-counts at reasonable communication traffic cost in M-P2P networks as compared to a recent existing scheme. In a mobile ad hoc peer-to-peer (M-P2P) network, mobile peers (MPs) interact with each other in a peer-to-peer (P2P) fashion [1]. Proliferation of mobile devices (e.g., laptops, PDAs, mobile phones) coupled with the ever-increasing popularity of the P2P paradigm (e.g., Kazaa, Gnutella) strongly motivate M-P2P network applications , which facilitate MPs in sharing information on-the-fly. For example, an application could involve an MP looking for an available parking slot within 1 km of its current location. MPs in the vicinity can collect information about available parking slots and charges, and then they can inform the brokers. The broker can then provide the available parking slots to the query-issuing MP in terms of price or distance (from the user's current location). Note that the parking slot availability information has to be current. Incidentally, although we consider brokers, the nature of the networking environment is still ad hoc in the sense that the peers can move and they can change their brokers. Hence, the presence of brokers does not make our environment completely structured. In a similar vein, a user could look for a restaurant with ''happy hours'' (or ''manager's special hours'') within 1 km of her current location. A broker can facilitate such queries by soliciting information from the peers moving in the vicinity of the query location. Similarly, an …