Research On Data Forwarding Technology For Opportunistic Networks

With the rapid development of network technology，the wireless communicationtechnology becomes more and more important in our everyday life. However，due to avariety of reasons, the wireless network can not be completely connected in manycases. But it does not mean that communication can not happen since the network isnot completely connected. So opportunistic networks come into being in these cases.Opportunistic network doesn’t require the network being compeletely connected, themesseges can be sent from the source node to the destination node successfullythrough the mobility of nodes, data storage and data forwarding. It has become a hotissue in opportunistic networks that how to forward the message from the source nodeto the destination node with higher success rate, smaller delay and less informationredundancy.At present, there exist no data forwarding mechanisms which can used for allkinds of situations. Usually, different merchanism will be chose on different occasion.An efficient method is proposed by this paper to solve the System Black Hole problemwhich exists in H-EC, and an original method is proposed to divide messages intosmall data blocks at the same time. Based on these existed works, a new forwardingapproach called EH-EC (Enhanced Hybrid Erasure-Coding) is proposed and achievedin this paper. Theoretical analysis and simulation results show that messages can betransmitted by EH-EC from source node to destination node with lower delay andhigher delivery rate than H-EC by the OMNET++platform, but only a few routerredundancies will be increased.The contents of this article are as following:(1) The national and international backgrounds of the subject are summarized.(2) Some classical data forwarding algorithms of opportunistic networks areintroduced, and the advantage and disadvantage of these algorithms are analysized topropose new data forwarding merchanism.(3) The H-EC algorithm is descibed, and the three problem of H-EC are alsointroduced, and some methods to solve the three problem are proposed at the sametime..(4)Based on EH-EC, a experiment platform is designed to test the transformperformance of the EH-EC.