EFFICIENT INCENTIVE-BASED ROUTING IN DTN USING COALITIONAL GAME THEORY

Abstract

Delay Tolerant Networks(DTNs) differ from the traditional Ad-hoc networks in its main characteristic function. DTNs are opportunistic networks in which there exists no complete end to end paths between the nodes. In view of the limited connectivity, DTNs rely upon the store carry and forward approach for communication. DTN is a well researched topic and finds large number of applications in daily life. The applications of DTN vary from space communication, smart city application to wildlife study. With the need of a working robust and efficient communication network in areas of limited connectivity, DTNs belong to the most sought and researched topic in networks. The study of behaviour of DTN nodes has been considered as a good area in DTNs by many of the researchers. Nodes may not always behave rationally and in a cooperative manner for network efficiency. Some of the network nodes may act selfishly to spend its resources such as buffer space or energy, for message transfer. These unwanted activities of the nodes hamper the smooth working of the network. With appropriate incentive, Tit-For-Tat (TFT) and game theoretic approaches these negative aspects of DTN nodes could be nullified. In this work, focus has been given to present a protocol based on coalitional game theory. Selfishness are induced on the basis of message drop, hence buffer space of a node plays as a good parameter in efficiency. Game theory has been identified and applied as a potential conflict resolution candidate in communication networks. Coalition game theory targets those problems in which the players of Efficient Incentive-Based Routing In DTN Using Coalitional Game Theory 2016 v the game group together, achieve the intended aim and share the reward points among themselves. Among different solutions existing in coalitional game theory for the reward division, the Shapley value concept emerges as a plausible concept providing appropriate shares to the players. In the proposed research work, coaltion game formation with shapley value credit division is implemented. Also the idea of grand coalition is discussed and simulated for comparison. A new routing protocol incorporating the idea of encounter history, named as Encounter protocol, is proposed. Relay selection is based upon the coalition game theory and the credit division, for avoiding selfishness, is implemented according to Shapley value. Extensive simulations have been performed as a part of the work. Comparisons have been made to existing benchmark algorithms which throw light upon the protcol’s efficiency. Also by simulating two selfishness based protocols, the proposed work shows better efficiency and implementation capability in the current scenario. To provide a better comparison covering wider aspects, a less used comparison criteria, energy dissipation, is also included as a part of the research work.