Research On MANET’s Node Cooperation Enhancement Scheme Incorporating Diversity Techniques

Most of the existing network operations in MANETs assume that mobile nodes owned bysame or different users will follow prescribed protocols without deviation, however, due tothe ad-hoc inherent characteristic issues ICI: like open structure topology, no infrastructure,scarcely available battery-based energy, short of availability of bandwidth (network resources)which significantly depredated network performance under fading channels, poor wirelesschannels, requirement of high transmission power single-hop routing which consequentlycauses increased interference, nodes during network operation tend to misbehave due toseveral reasons resulting from network inherent issues. These nodes’ misbehaving can eitherbe intentional misbehaving (caused by nodes themselves) or unintentional misbehavingmostly caused by network inherent issues (wireless environment impairments). Intentionalmisbehaving as been slightly resolved by using Incentive mechanisms but that of theunintentional misbehaving for maximum node cooperation is not.Hence, stimulating and enforcing the cooperation among nodes to resolve unintentionalmisbehaving becomes a very important issue, and the issue is not just only to developmechanisms (incentive procedures) to enforce cooperation among nodes but to addressnetwork inherent challenging issues (ICI) that made nodes not to cooperate i.e. misbehaving.Several different incentive mechanisms approach: virtual currency mechanism, reputationbased mechanism and game theoretic mechanism (IEEE802.11based) have been developedto address nodes non-cooperation or deal with the non-cooperative behaviors of mobile nodesin MANETs, but they have failed or not done much because they do not show any networkinherent issues improvements; it is known that no amount of incentives can better improvesthe relaying channels of MANETs due to its topology. Needed cooperation can’t just beenforced by using these incentive procedures but by incorporating some combinationdiversity techniques which can help in reducing or improving the wireless constraints natureof MANETs.In this paper we propose a complete system framework for MANETs Noco-DCDTMACnode cooperation mechanism incorporating diversity techniques which first address thenetwork inherent issues of MANETs by creating multichannel medium, cooperative channelsby conveying packets from source to a destination through multiple intermediate nodes withhigher order modulation to improve channel relaying and routing by achieving significantpower savings, getting rid of unintentional misbehaving attitude of nodes, and pave a way toenhance effective nodes cooperation. In addition we propose Decentralized Routing Protocol(DRP) based on AODV using multiuser diversity for efficient channel discovery andselection. The simulation results show that with the proposed scheme, ICI which are the major causeof ad-hoc node misbehaving are addressed and solved by the tremendous throughputimprovement in the relaying and routing of data packet, less delay in transmission and higherpacket traffic delivery ratio. It also shows a lesser percentage of node misbehaving comparedwith incentive mechanisms. With this work MANETs can be robust against nodes’unintentional misbehaving, and the performance of the network was enhanced in many foldswhen compared to other existing schemes.