机会网络中的自适应喷雾路由及其性能评估.pdf

计算机研 究与发展 ISSN 1000—1239／CN 11-1’7|P JournalofComputerResearchandDevelopment 47(9)：1622—1632，2010 机会网络 中的 自适应喷雾路由及其性能评估 徐 佳 。李千目 张 宏 刘凤玉 (南京邮电大学计算机学院 南京 210046) (南京理工大学计算机科学与技术学院 南京 210094) (xujia@mail．njust．edu．cn) PerformanceEvaluationofAdaptiveSprayRoutingforOpportunisticNetworks XuJia一。LiQianmu。。ZhangHong。，andLiuFengyu。 (ComputerInstitute，NanjingUniversityofPostsandTelecommunication，Nanjing210046) (InstituteofComputerScienceandTechnology，NanjingUniversityofScienceandTechnology，Nanjing210094) Abstract Opportunisticnetworksaresparsewirelessnetworkswheremostofthetimetheredoesnot existcompletepathfrom thesourcetothedestination．Themessagescanbeforwardedtodestination ultimatelyin themannerofasynchronoustransmission which relieson the contactopportunities betw,eennodesinopportunisticnetworks．Thischaracteristicsofopportunisticnetworkscangreatly extend the space—time metric of information collection and processing． Although opportunistic network often shows large delay，it doesn’tmean that itisnotnecessary to implementquality assurance．Forexamples，electronicnoticeincampusnetworksandshort—term weatherinformationin largenationalparks mustbe forwarded with specific delay． On theother hand，as the access networks，configurationandforecastforQoSarealsonecessaryinordertoprovideacceptableservice (suchase—mail)in opportunisticnetworks．Henceopportunisticnetworksmustprovideacceptable andresilientservice in the face of challenging environments． According to the shortcoming of traditionalsprayroutingindynamicopportunisticnetworks，aclassofadaptivespraymechanismsare proposedinthispaper．Adaptivespraymechanismsuserelaynodestomakespraydecisionsinorderto apperceiveandreacttothechangeofnetwork conditionsexquisitely，andareleast—costdelay-bounded routingprotocolsunderspecificspraymechanisms．Theoreticanalysisofadaptive spray routing at