分布式VOD系统中集群视频服务器的设计与实现

华中科技大学硕士学位论文分布式VOD系统中集群视频服务器的设计与实现姓名：昌玉芳申请学位级别：硕士专业：通信与信息系统指导教师：黄本雄20060425IVODVODPCVODVODVODVODLinuxLinuxVirtualServer(LVS)LVSVODLinuxIIAbstractForrecentyears,tosatisfytheincreasingaccessloadingrequirementsofInternetvideoservices,VODsystemislikelytofaceanumberofchallengesatboththenetworkandserverside.Withthenetworkbandwidthincreasingmuchfasterthantheservercapacity,moreandmorebottleneckswillbeobservedontheserverside.Clusterbecomesacomparativeidealmethodforenhancingtheperformanceofvideoserverbecauseofitsloadbalancing,high-availabilityandscalability.ThispapermadeasystematicresearchoftheVODvideoserverclustersystemdesignandimplementation,andtriedtouseadistributedarchitecturetomakecommonPCsavideoserverwithloadbalancing,high-availability,scalabilityandhigh-performanceforthepurposeofbuildingalarge-scalevideoserversystem.AfteranalyzingthebasicstructureofVODsystemandclustertechnology,weproposedaVODvideoserverclustermodelwhichisconsistingofWideAreaNetwork(WAN)frameworkandLocalAreaNetwork(LAN)framework.ThedistributedVODsystemunderWANframeworkincludesacenterandseveralsub-centers,andeverysub-centerworksinaLANwhichhasavideoserverclustersysteminit.Avideoserverclusteralsoincludestwoparts:aclustermanagementnodeandseveralvideoservicenodesFirstly,thedesignforloadbalancing,high-availabilityandscalabilityofLANvideoseverclustersystemisdescribed.Loadbalancingisimplementedbytheloadbalancingschedulingcomponent,whichisontheclustermanagementnodeofvideoseverclustersystem,byusingcertainloadbalancingalgorithm.ThepaperpresentsaloadbalancingalgorithminapplyingtoVODserverbasedonastudyofcommonloadbalancingalgorithmswhileconsideringthecharacteristicsofvideofiles,likestorage,playingmodeandstreamrate.High-availabilityschemeofclustermanagementnodeandvideoservicenodearediscussed.Toavoidsinglepointoffailure,clustermanagementnodeusesabackup.Andvideoservicenodeusesheartbeatmessagetoconnectwithclustermanagementnodewhichcandetectandtakeoveritsfailure.Dynamicextensioncanaddvideoservicenodeswithoutchangingthecurrentrunningstatus.Inaddition,schemesforloadbalancingandscalabilityofavideoserverappliedtoWANarediscussed.TheoperatingsystemofVODserverisLinux,soLinuxvirtualserver(LVS)isusedforbuildingthevideoservercluster.TheapproachofimplementingaLVSvideoserverclusterisdescribeddetailedly.Italsogaveafullimplementationofinteractivefunctionsforclustermanagementnode,videoservicenodeandclientside.Throughtesting,itshowstheloadbalancing,high-availabilityandscalabilityofthisvideoserver,andprovesthatusingtheclusterschemecanachievetherequirementforimprovingperformance.KeywordsVOD;videoserver;distributed;cluster;LVS;loadbalanceI_____111.1Web[1][2](VOD)VODVideoOnDemand[3]Internet[4]InternetVODCPU[5]21.2[6]1.2.1PCPCPCOK50PCI/OATMDVB-AS1QAM[7]MicrosoftMediaPlayerServerRealNetworksRealServerAppleQuickTimeStreamingServerDarwinStreamingServer[8]SYNLEADixJetStreamingVODSystem300nCubeMediaCube431.2.2VODI/O[9][10]1-1VOD1.5MbpsMPEG43001.5Mbps300=450MbpsPCPCPCInternet1-1VOD10001.5Mbps10001.5Gbps1000VOD[11][12][13][14][15]41.2.3CPU1-2[16]InternetInternet[17]1-2[18]IP(VIP)[19]5PC[20]PCPCVOD[21]Tiger[22]Elvira[23]IBMTigerShark[24]WanLan[25][26][27][28]VODPC[29]VODVOD1.3VODWindowsKTVVODVODLinuxLinux61.4VODVODVODLinuxLVSLinuxLVSVODLinuxVODLVSLVSLVSVOD72VODLinux2.12.1.1VODVideoOnDemand[30]VOD[31]VOD(//)VOD2-1VOD:DVDDVDdrive2-1VOD81VODVCR[32](1)(2)(fitter)(3)(4)VCR(5)2VOD(IP/ATM)(CATV)(PTSN)IPATMIPADSLHFC(1)MPEG-11.5MbpsMPEG-23-100MbpsMPEG-45kbpsl0Mbps(2)QoS(3)IPUDPCable9(4)IPIPCableIPCable3(Set-top-Box)2-2VODCPUMPEG-2ADSL()ATM()HFC()/TV2-2(1)IPPCCable(KB)(2)VCR(3)102.1.2VODRTP/RTCP/RSVP[34]802.1pRTPRTCPRTSPRSVPRTPInternetRTPUDPRTPRTPRTCPRTCPRTCPRTPRTCPRTSPHTTPHTTPRTSPRSVP(QualityofService)RTSPRTPRTPRTCPRTSP[33]2.22.2.1PC()11[35](ClusterSystem)12TCP/IP34[36]12Web2.2.2[37][38][39]2.2.3[40][41][42]12(RoundRobin)131N3(WeightedRound-Robin)4(Least-Connection)[43]11TCPTIME_WAITTCPTIME_WAIT2TIME_WAIT5(Weighted14Least-Connection)62.2.4OSI[44][45]1DNS(DomainNameServer)[47]DNSDNSdlbDNS(dynamicloadbalanceDNS)IP“Ping”IPRoundRobin()IP“Ping”“pingmail.sina.com.cn”IP2OSI/RMApacheProxyPass15ASPredirection3IPIPIBMInteractiveNetworkDispatcherCiscoLocalDirectorAlteonACEDirectorF5BigIP2.2.5Linux19985LinuxVirtualServer[48]LinuxLinuxVirtualServerLinuxLVSLinuxVirtualServer2-3LVSIPIPIPVS[49]Layer-7KTCPVS16E-CommerceGeneralNetworkServicesClusterManagementKTCPVSIPVS2-3LinuxLinux[50]Linux(LVS)2.2.5.1LVSLVSLVS[45]IPIP(NetworkAddressTranslation)IP(IPTunneling)(DirectRouting)IP1VirtualServerviaNetworkAddressTranslation(VS/NAT)IP/IP/TCP/IPIP2VirtualServerviaIPTunneling(VS/TUN)NAT17IPIPIPVS/TUN10IP3VirtualServerviaDirectRouting(VS/DR)VS/DRMACVS/TUNVS/DRIPIPIPVS2.2.5.2LVSLVS2-4(loadbalancer)IP(IP)(serverpool)(sharedstorage)18USERInternet,IntarnetLoadBalancerRealServer2LoadBalancerBackupRealServernRealServer1RequestsheartbeatVirtualIPAddress…DatabaseNetworkFileSystemDistributedFileSystemLoadBalancerServerClusterStorage2-4LVS(SingleEntryPoint)IPIPLinux100MbpsMyrinetCigabit[46]19WebCacheMailMedia