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IVoD(VideoonDemand)VoDVoDVoDLRULeastRecentlyUsedIIVoDVoDVoDP2P(PeertoPeer)P2PIIIInvideoservicefield,thedevelopmentofdigitalvideotechnologyandcommunicationstechnologybringspeoplenotonlytheimprovementofvideoquality.Thechiefattractionisthatpeoplecouldprocessandgettheinformationmoreexpediently.Peoplealwayswanttogetmorecolorfulinformationservice.Absolutely,videoondemandisoneofthemostimportanttechnologies;andithasawideapplication.Although,thenetworkbandwidthisincreasedrapidly;thecapacityofmediaserverisimprovedcontinuously;andtheperformanceoftheuser’sterminalunitisenhanced.Theycannotkeepupwiththeincreaseoftheuser’srequirementsinthevideoondemandservice.Howtoprovideaninstantvideoserviceinlarge-scaleVoDsystem;andhowtoprovideawirelessVoDservicearethechallengestous.Inthisthesis,wefocusontwoaspectsoftheVoDtechnology.Oneisthevideostream-broadcastingscheme.Theotheroneisthearchitectureofthenew-styleVoDsystem.Weanalyzethecharacteristicandflawofthecurrenttechnologyfirstly.Andthenweproposeournewschemeandmethod.Weusemathematicstoolsandcomputersimulationasourmaininstrumenttoanalyze,evaluateandvalidateourresearchwork.Firstly,weanalyzetheperiodicbroadcastingtechnologydeeply.Basedonit,weproposeamodifiedfastbroadcasting(MFB)scheme.Bescauseofusingextendedbroadcastchannelandschedulingthevideosegmentsinchannelsartfully,theMFBschemeneedslessbufferrequirementsanddiskI/Orequirementsthanthefastbroadcasting(FB)schemeinthesameservicedelay.AnduserscanalsosharetheVoDserviceinashortservicedelayeventheirterminalunitswithoutlocalstorage.Videoproxyserverisoneofthemaintechnologiesinlarge-scalestreammediadistributingsystemforshieldingthetransmissiondelayofmultimediaovertheInternetandlighteningthecontextserverload.Wediscussthemethodofmultimediastreamsdistributionbasedonproxyserver.Proxystorageisdividedintostaticanddynamicstorage.Linearprogrammingisusedtoinitializethestaticstorageandspecialcachereplacementarithmeticisusedtomanagethedynamicstorage.Thesimulatedresultsshowthatthemethodgetsahighdemand-successratio,byte-hitratioandalowvideodemanddelay.Inthelastpartofthisthesis,weproposetwoVoDsystemmodelsinthenewapplicationcircumstance.Weweddigitalterrestrialtelevisiontechniqueto802.11gwirelesslocalareanetworkstechnique;andproposeahybridwirelessVoDsystemmodelforthefirsttime.Theclientaccessarithmeticandaclient“densitysensitivity”IVcache-selectiveschemearediscussedinourwirelessVoDsystem.Apeer-to-peerlivevideodistributingmodelisproposedintheend.Becauseofusingmultipledescriptioncodingtechnologyandingenioustransmissionscheme,thislivevideodistributingmodelmakeeffectiveuseofnetworkbandwidthandhasagoodrobustnesstothenetworkbandwidthchanging,packagelosingandtransmittingdelay.VoD,PeriodicBroadcasting,ProxyCache,MobileNetworks,P2P,MDC_____11050050501000OK10002VoDNVoDTVoDIVoDNVoDNearVideoonDemand121010TVoDTrueVideoonDemandIVoDInteractiveVideoonDemandVCR-VideoCassetteRecorderVCR2090VideoonDemandVoD1986BellSouthVoD1993BellAtlanticMPEGI2000Nynex19941214TimeWarnerFullServiceNetworkIBM19957Microware3/DigitalAudio-VisualInteractiveDecoderDAVIDWindowsCE17KTNEC1996SSIIMITV19971999VoDI/OI/OCPUI/OI/OI/OI/O4I/OI/OI/OI/ORAIDRAID5I/O6I/O7CPUMPEG510VoDVoDVoDI/OVoDVoD[1]VoD[2][3]8I/OI/ORAID[4]Cache[5]VoDLFRULeastFrequencyandRecentlyUsedPLFUPeriodLeastFrequencyUsed[6]CacheLFRUPLFULFULeastFrequencyUsedCache[7,8,9,10]predict-and-enforce[11,12,13]VoDVoDVoDTVoDTVoDTVoDVoDVoDVoDVoDbatching[14,15,16,17]chaining[18,19]periodicbroadcasting[20-33]patching[34-38]andpiggybacking[39-42]batching9Danfirst-come-first-serveFCFSmaximumqueuelengthMQL[14]AggarwalmaximumfactoredqueueMFQ[17]chainingvirtualbatchingSheu[28,29]periodicbroadcastingNVoDpyramidbroadcasting[22,23]skyscraperbroadcasting[25]GreedyDisk-ConservingBroadcasting(GDB)[29]I/O[22,23]PyramidSchemePyramidScheme[43,44]FastBroadcastingSchemeFB/(21)kD-Dk[45]FBBorrow-and-ReturnModel”FB[46,47]PAGODABroadcastingScheme”k(/2)1/(4(51)kD--k/2/(2(5)1)kD⎣⎦-[27]StaircaseSchemeFS[26]harmonicscheme[48,49]FrequencySplittingScheme10patchingpatchingchannelpatching[35]patchingpatchingpiggybackingpatchingLiao[34],Hua[35]Cai[36]batchingpatchingOh[50]batchingskyscraperLargestAggregatedWaitingTimeFirstLAWMFQOhSkyscraperVoD[51]QoS[52][53][54]Sang-HyunParkMPEGI[55]GuoXueVoD[56][57,58,59]VoD[60,61]1196VoDVoDVoDDVB-HDigitalVideoBroadcastingHandheldAdHocVoDP2PMDCMultipleDescriptionCoding1.MFBModifiedFastBroadcasting2.LRULeastRecentlyUsed3.DVB-HVoD124.P2P131.4.2VoDS.ViswanathanT.Imielinski(PyramidBroadcasting)[22]Aggarwal,WolfYu(Permutation-basedPyramidBroadcasting)[23]HuaSheu(SkyscraperBroadcasting)[25],EagerVernon(DynamicscraperBroadcasting)[31]Gao,KuroseTowsley(GreedyDisk-conservingBroadcasting)[29]JuhnTseng(HarmonicBroadcasting)[26](StaircaseBroadcasting)[27]SatichChand,HariOm(ModifiedStaircaseBroadcasting)[62](PyramidBroadcasting)(SegmentizedBroadcasting)I/OI/OKi()1411(1)111KiiLiLLiKaaa--⎧=⎪-⎪=⎨⎪≤⎪⎩(2.1)a1a2.1.1.212,,,KLLLL(2.1)1KiiLL==∑MBKB/Ki12,,(1)MiiiSSSiK≤≤LjiSjibaiL1/iiLMbLBK+⋅⋅≥(2.2)1iiLLa+=⋅(2.2)aBbMKa≤(2.3)aPB:aPB:b1.PB:aBKbMe=⎡⎤eaBbMKa=2.PB:bBKbMe=⎣⎦ea