计算机网络技术的历史和新进展

计算机网络技术的计算机网络技术的历史和新进展历史和新进展„„高速计算机信息网络是信息社会高速计算机信息网络是信息社会的神经和血管的神经和血管„„体系结构：网络的骨架和神经体系结构：网络的骨架和神经„„协议：网络的心脏和血液协议：网络的心脏和血液主要内容主要内容„„网络概述网络概述„„InternetInternet的发展和成功经的发展和成功经验验„„计算机网络技术的历史回顾计算机网络技术的历史回顾„„国际高速计算机网络研究计国际高速计算机网络研究计划划„„中国高速计算机网络研究计中国高速计算机网络研究计划划WhatisaNetwork?WhatisaNetwork?fromendsystempointofviewfromendsystempointofview„„Networkoffersaservice:moveinformationNetworkoffersaservice:moveinformation••bird,fire,messenger,truck,telegraph,telephone,Internetbird,fire,messenger,truck,telegraph,telephone,Internet……••anotherexample,transportationservice:moveobjectsanotherexample,transportationservice:moveobjects„„horse,train,truck,airplane...horse,train,truck,airplane...„„Whatdistinguishdifferenttypesofnetworks?Whatdistinguishdifferenttypesofnetworks?••TheservicestheyprovideTheservicestheyprovide„„Whatdistinguishtheservices?Whatdistinguishtheservices?••latencylatency••bandwidthbandwidth••lossratelossrate••numberofendsystemsnumberofendsystems••serviceinterface(howtoinvoke?)serviceinterface(howtoinvoke?)••otherdetailsotherdetails„„reliability,reliability,unicastunicastvs.multicast,realvs.multicast,real--time,messagevs.byte...time,messagevs.byte...WhatisaNetwork?WhatisaNetwork?InfrastructureCentricViewInfrastructureCentricView„„ElectronsandphotonsascommunicationmediumElectronsandphotonsascommunicationmedium„„Links:fiber,copper,satellite,Links:fiber,copper,satellite,……„„Switches:mechanical/electronic/optical,Switches:mechanical/electronic/optical,crossbar/Banyancrossbar/Banyan„„Protocols:TCP/IP,ATM,MPLS,SONET,Ethernet,Protocols:TCP/IP,ATM,MPLS,SONET,Ethernet,PPP,X.25,FrameRelay,AppleTalk,IPX,SNAPPP,X.25,FrameRelay,AppleTalk,IPX,SNA„„Functionalities:routing,errorcontrol,congestionFunctionalities:routing,errorcontrol,congestioncontrol,QualityofService(control,QualityofService(QoSQoS))„„Applications:FTP,WEB,Xwindows,...Applications:FTP,WEB,Xwindows,...TypesofNetworksTypesofNetworks„„GeographicaldistanceGeographicaldistance••LocalAreaNetworks(LAN):Ethernet,TokenLocalAreaNetworks(LAN):Ethernet,Tokenring,FDDIring,FDDI••MetropolitanAreaNetworks(MAN):DQDB,MetropolitanAreaNetworks(MAN):DQDB,SMDSSMDS••WideAreaNetworks(WAN):X.25,ATM,frameWideAreaNetworks(WAN):X.25,ATM,framerelayrelay„„InformationtypeInformationtype••datanetworksvs.telecommunicationnetworksdatanetworksvs.telecommunicationnetworks„„ApplicationtypeApplicationtype••specialpurposenetworks:airlinereservationspecialpurposenetworks:airlinereservationnetwork,bankingnetwork,creditcardnetwork,network,bankingnetwork,creditcardnetwork,telephonytelephony••generalpurposenetwork:Internetgeneralpurposenetwork:InternetTypesofNetworksTypesofNetworks„„RighttouseRighttouse••private:enterprisenetworksprivate:enterprisenetworks••public:telephonynetwork,Internetpublic:telephonynetwork,Internet„„OwnershipofprotocolsOwnershipofprotocols••proprietary:SNAproprietary:SNA••open:IPopen:IP„„TechnologiesTechnologies••terrestrialvs.satelliteterrestrialvs.satellite••wiredvs.wirelesswiredvs.wireless„„ProtocolsProtocols••IP,AppleTalk,SNAIP,AppleTalk,SNA计算机网络发展历史回顾计算机网络发展历史回顾„„七十年代的计算机网络七十年代的计算机网络−−X.25X.25分组交换网：各国的电信部门建设运行分组交换网：各国的电信部门建设运行−−各种专用的网络体系结构：各种专用的网络体系结构：SNASNA，，DNADNA−−InternetInternet的前身的前身ARPANETARPANET进行实验运行进行实验运行„„八十年代的计算机网络八十年代的计算机网络−−标准化计算机网络体系结构：标准化计算机网络体系结构：OSIOSI−−局域网络局域网络LANLAN技术空前发展技术空前发展−−建成建成NSFNETNSFNET，，InternetInternet初具规模初具规模„„九十年代的计算机网络九十年代的计算机网络−−InternetInternet空前发展空前发展−−WebWeb技术在技术在Internet/IntranetInternet/Intranet得到广泛应用得到广泛应用主要内容主要内容„„网络概述网络概述„„InternetInternet的发展和成功经的发展和成功经验验„„计算机网络技术的历史回顾计算机网络技术的历史回顾„„国际高速计算机网络研究计国际高速计算机网络研究计划划„„中国高速计算机网络研究计中国高速计算机网络研究计划划TheInternetTheInternet„„Globalscale,generalpurpose,Globalscale,generalpurpose,heterogeneousheterogeneous--technologies,public,technologies,public,computernetworkcomputernetwork„„InternetProtocolInternetProtocol••openstandard:InternetEngineeringTaskopenstandard:InternetEngineeringTaskForce(IETF)asstandardbodyForce(IETF)asstandardbody••technicalbasisforothertypesofnetworkstechnicalbasisforothertypesofnetworks„„Intranet:enterpriseIPnetworkIntranet:enterpriseIPnetwork„„DevelopedbytheresearchcommunityDevelopedbytheresearchcommunityHistoryoftheInternetHistoryoftheInternet„„7070’’s:startedasaresearchproject,56kbps,s:startedasaresearchproject,56kbps,100computers100computers„„8080--83:ARPANETandMILNETsplit,83:ARPANETandMILNETsplit,„„8585--86:NSFbuildsNSFNETasbackbone,links686:NSFbuildsNSFNETasbackbone,links6Supercomputercenters,1.5Mbps,10,000Supercomputercenters,1.5Mbps,10,000computerscomputers„„8787--90:linkregionalnetworks,NSI(NASA),90:linkregionalnetworks,NSI(NASA),ESNet(DOEESNet(DOE),),DARTnetDARTnet,,TWBNetTWBNet(DARPA),(DARPA),100,000computers100,000computers„„9090--92:NSFNETmovesto45Mbps,16mid92:NSFNETmovesto45Mbps,16mid--levellevelnetworksnetworks„„94:NSFbackbonedismantled,multipleprivate94:NSFbackbonedismantled,multipleprivatebackbonesbackbones„„Today:backbonesrunat2.5/10Gbps,10sToday:backbonesrunat2.5/10Gbps,10smillionscomputersin150countriesmillionscomputersin150countriesGrowthoftheInternetGrowthofthe