The Research On Routing Protocols For Opportunistic Networks Based On Network Coding

As a new wireless network, opportunistic networks can be widely used in many aspectsof society, such as InterPlaNet, long-distance radio links, free-space optical communication,Land Mobile Networks and Military Ad hoc Networks. It has the characteristics of a linkintermittently connected, low data transmission rate, high-delay and node limited resources.Because the wireless link has the feature of random discontinuity and the communicationterminals could not establish a reliable end-to-end path, the existing TCP/IP protocol cannotrun on opportunity networks. At present, it has been carried out all kinds of new technologyfor opportunity networks and routing protocol is the focus of the research.This paper outlines the concept and the feature of opportunistic networks, thenanalyzes and classifies the existing in some typical routing protocols of opportunisticnetworks, proposes two improved protocols of Spray and Focus(SF) which is an existingopportunistic networks routing protocol: Spray and Focus based on Separation Time(SF-ST)and Spray and Focus based on Random Linear Network Coding(SF-RLNC), and then usesOpportunistic Networking Environment(ONE) to evaluate the protocols’ performance.This paper discusses the traditional routing protocols SF of opportunistic networksdetailedly, in consideration of the blindness to choice the intermediate nodes of SF protocolduring the spray stages, in the routing choice without any restrictions on this defect,improve SF, propose a new improved routing protocol SF-ST, SF-ST protocol agreement"separation time" throughout the entire routing process in order to achieve the purpose ofaccurately choose the next hop node to forward packets. Change in network size and nodedensity, the agreement can be a good control network overhead, has good scalability.Furthermore, the agreement for the SF-ST did not take full advantage of the most preciousopportunistic networks nodes meet the opportunity to the data forwarding meet this defecthas a certain blindness, the use of random linear network coding ideas to improve theagreement of the SF-ST proposed based on random linear network coding ideas theSF-RLNC agreement, the agreement used copy routing based on network coding andforwarding strategies based on utility value the former well balanced network overhead,which can effectively reduce the forwarding number, ultimately maximize the opportunistic networks performance.We use the ONE simulation platform to simulate and analysis the SF-ST protocol andSF-RLNC protocol. Simulation results show that the new two protocols have a goodperformance on improving the success rate of packet transmission and data delivery rate,reducing the transmission time, reducing the average number of hops, and reducing theaverage energy consumption.