Delivering quality of services for media streaming over IP networks

Abstract

AnanalysisofQoSfactorsinmultimediaprotocolssuchasRTP(RealTimeProtocol),RTCP(RealTimeControlProtocol),RTSP(RealTimeStreamingProtocol)andMGCP(MediaGatewayControlProtocol),hadidentifiedthatimportancehavenotbeenprovidedtolatencyeffects,throughputandfaulttoleranceissues.Realtimemediastreamingapplications suchasMediaConferencing,VideoOnDemand,AudioPlay-outonDemand,requirehighQoSfactors.MultimediaprotocolslackinadequatesupportforguaranteeofperformancemeasuresofQoSmetricsandtomanagecomplexresourcecomponentsinvolvedinruntimeforservingaudio/videotransfer overdistributedIPnetworks.ThisthesisaimstoprovideaneffectiveandoptimalQoSsolutionformediastreamingapplicationsoverIPnetwork.Theresultantnetworkparameterssuchasnumberofpacketslost,jitterandend-to-enddelaydeterminethequalityofservice(QoS)ofmediastream.Thesefactors,whichtamperthequalityofstreamingmedialeadstoreducedthroughput,increaseinlatencyeffectandworstMOS(MeanOpinionScore)value.Theworkprovidesthreedifferentschemes,whichfocusonreducingmediapacketloss,minimizedelayinmediaplay-out,avoidcongestionandprovideanend-to-endQoSsupport.ThefirstschemeMe-PLM(MediaPacketLossMinimization)isadvancementovertheexistingREDandSF-BLUEcongestionmanagementschemes.Me-PLMschemereducesmediapacketlosswithconsiderableincreaseinthedelaytimeatreceivingendforpacketplay-out.ThesecondschemeMe-Trff-Schl(MediaTrafficScheduler)controls ivmediatrafficflowatgatewaysandroutersthusmanagingtheflowofmediatraffic.Thismethodprovidesaminimaltimedelayforplay-outofmediapacketsatreceiverend,thushandling jittereffectively.ThethirdschemeMe-TRAP-Q(MediaTrafficAdaptiveQoSProvider)isanadvancementofMe-TrffSchlmethod.Thisschemeisheuristic,adoptingadaptiveschedulingstrategytrafficschedulingapproach,whichworksoncomplexpolicymanagementstructure.Thisschemereducesthedelaytimeformediaplayoutatreceiverend,minimizesmediapacketlossandminimizesend-to-enddelay.Further,anovelobjectorientedengineeringapproachforprovidinganend-to-endQoSinmediastreamingnetworkisproposedasMe-ADO-Q(ObjectOrientedEngineeringandDistributedApproachofQoSapproachforMediaStream).Theobject-orientedapproachmanagesintermediatemediacallsessionresourcesandhandlesmediatrafficusinganytrafficmanagementschemesuchasMe-TRAP-Q,Me-TrffSchl,DiffServ,Best-Effort.Me-ADO-Qisobjectorientedanddistributedinnature,whichmonitorsandmanagesallcomponentsinvolvedinsettingupacallinamediatransferover networkforanend-to-endsetup.Thearchitecturalmodelhasbeenexplained usingVideo-On-Demandvideotransferapplication,whichdemandsmaximumbandwidthandmemoryfortransferofvideoframesovernetwork.Me-ADO-Qaimsatprovidingcoordinatedfunctionalitybetweenvariouscomponents involvedinmediatransferovernetwork.Me-ADO-Qusesthecomplexmethodologyof“rule”basedPolicyManagerandadaptivecontrolmechanismsthatcanco-operateintelligentlyinlarge-scalenetworkstosupportQoSobjectives.Me-ADO-Qapproachalso Vincorporatespredictivereservationmethods,admissioncontrolatgatewaysformediapacketsandTrafficPolicingmethodstoprovideQoSforrealtimemediastreamsforbandwidthsensitiveapplicationsoverCDNs.ThemodelhasbeendevelopedusingObjectOrientedMethodology(usingCORBA)controllingovernetworkcomponentsinstate-fullorstate-lesstype.Mediapacketstransferredisassignedhierarchybasedonpolicymanagementandservicingarchitectures.Theresultshavebeenobtainedusingvarioustest-bedmethodspreparedwithchangingbandwidthvaluesforworst-caseconditions.Thetestbedsusedforinvestigatingthevariousschemesdevelopedhavebeenpreparedonsimulation.Alltheproposedschemesdevelopedhavebeentestedwithexistingprovedresultsincomparison.Ingeneralthedissertation worktogetherprovidessupportfordifferentiatednetworkarchitectureofdeterministicaswellpredictablequalityofserviceofmediatransferoverIPnetworks