Mobile Delay Tolerant Network Routing Protocol Research

In recent years, the development of wireless communication technologies leads tothe emergence of a large number of short-range wireless communications equipmentwhich characterized with small size, low cost and smart, and the gradual rise of delaytolerant network (referred to as mobile DTN). Mobile DTN is a new kind of networkmodel; it is abstracted from wireless sensor network. This kind of model can be appliedto some special circumstances, such as Terrestrial Mobile Network, Exotic MediaNetwork, medical care, monitoring animal behavior, forest fire alarm, intelligent traffic,etc. It has a high value of theoretical research and practical. Such network has high linkdelay, limited buffer memory space, and lacks of continuous energy supply. The end toend path of DTN disconnects frequently. Mobile DTN mainly relies on some relay nodeto transmit data message. So the traditional network protocol does not suitable for suchnetwork. The routing technology of mobile DTN has been a matter of difficulty, so therouting algorithm of mobile DTN is of great significance in promoting the developmentof wireless sensor networks.The main research object of this thesis is routing algorithm of mobile DTN. First,this thesis introduces the course of development and practical application of the mobileDTN, and key technologies and research results of mobile DTN. This thesis summarizessome existing DTN routing protocols and analyzes their key technologies and features.Second, this thesis introduces some concepts of the social network and analyzes basicfeatures of it. Third, this thesis analyzes the feasibility of combining routing strategywith some theories of Social Network. Forth, this thesis analyzes some classicalalgorithms that combined with the characteristics of social networks, such as SimBet,Bubble Rap and PROPHET, and discusses their advantages and limitations. Wecombined with their design philosophy, and crate a History travel model (HTM) whichreflects the individual node mobility features. Then, based on this model, a Position andHistory Association-based Routing Algorithm (PHA), which uses node deliveryprobability to give guidance for message transmission is proposed. The node deliveryprobability is calculated according to both the node’s current moving prediction and its history record, thus ensuring that the node can always forward the data to the node thathas a greatest probability of communicating with the given destination. Finally, simulatethe SimBet, Bubble Rap, PROPHET and PHA protocol, and compare PHA with theother protocols. The results show that the PHA algorithm can effectively improve theperformance of routing transmission.