Research On Routing Technology And Energy Efficiency In Delay And Disruption Networks

In Delay/Disruption Tolerant Networks,an upper bound of the propogation delay and a persistent bi-direction link is not required.Thus,DTNs is often considered as an effective extension to the existing network infrastructures and targeted to solve the problems that it is unable to communicate under extreme conditions.The applications of DTNs have been envisioned for Inter Planet Networks,Vehicular Ad hoc NETworks,Mobile Social Networks,and suburb networks for remote areas.Especially in the era of big data,with the increasing demand for uploading and downloading massive data and asynchronous communication,DTNs can make full use of all the nodes to forward data.The long delay and intermittent connectivity of link have caused many problems,such as the inaccurate network topology information and the inability to implement the end to end confirmation mechanism.DTNs usually follow store-carry-forward to complete packets transmission.The goal of DTNs routing is to achieve maximum delivery performance,without the knowledge of network's topology.In both space and terrestrial applications,terminals in DTNs are usually working with limited energy and can't be supplied in a timely manner.Therefore,energy efficiency is also a problem that needs to be focused on.This paper studies the routing technology and energy efficiency of DTNs.The main novel contributions of this paper are as follow:1.A social identity-based routing in DTNs,SIDBR is proposed.SIDBR optimizes the routing mechanism by using the social attributes of DTNs nodes.According to the identity attribute of the network node arising from social relationship,the definition of the social identity is proposed.The social identity and the tie strength of social relationship between the nodes are defined as the forwarding utility value of the routing protocol.The social identity is a static attribute,and the tie strength between nodes belongs to the dynamic attribute.Thus,it is a combination of static and dynamic social attributes and a one hop predication routing protocol.The protocol is designed and evaluated under simulation.It is verified that the protocol effectively improves delivery performance compared with some classic DTNs routing protocols.2.HURSE(A Hybrid Utility Routing considering Selfishness for Energy-constrained DTNs)is proposed.The protocol considers the social and individual selfishness of nodes with the tie strength of nodes as the utility of routing decisions.This paper proposes the definition of node selfishness satisfaction level,which can reflect how much the node is satisfied in the network.According to the evaluation,the protocol can reduce the invalid forwarding and the delivery cost while achieving better delivery performance.3.From the perspective of efficient data transmission and information security,PFC-DRP,a DTNs routing protocol based on percolation and fountain coding is proposed.The source data is coded by fountain code and transmits with different coding groups on multi-path percolation.The protocol can make full use of the available path in the network and achieve higher transmission rate and avoid the occurrence of congestion.The protocol also improves the security of data transmission.Data interception on single path will not be a serious threat to the leakage of total data.According to the simulation results,compared with other protocols,the protocol can achieve higher message delivery performance and reduce the overhead of delivery.It is an efficient DTNs routing protocol.4.A dynamic beacon message transmission mechanism based on energy efficiency,EE-SABS,is proposed.Under the mechanism,nodes can adapt and adjust the sending interval of beacon messages according to network state,thus improving the efficiency of node energy utilization.The mechanism can be applied to any DTNs routing protocol that obtains network information by sending beacon signals.According to the simulation results,the mechanism has universal applicability under several classic routing protocols,and the effect of the mechanism to the overall message delivery performance of the network is obvious when the node energy is limited.