乙太被動式光學網路上能支援多媒體服務之動態頻寬配置機制

DynamicBandwidthAllocationMechanismsforMultimediaServicesonEPON指導教授:吳和庭博士研究生：簡睿毅日期:2005/7/15OutlineBackgroundPassiveOpticalNetwork(PON)EthernetPassiveOpticalNetwork(EPON)Multi-PointControlProtocol(MPCP)MotivationDynamicBandwidthAllocationSchemeIPACT&DBAMDBAwithQoSSimulationResultConclusion&FutureWorkBackgroundThefirstmilestillremainsthebottleneckbetweenhigh-capacityLocalAreaNetworks(LANs)andthebackbonenetworkAnewtechnologyisrequiredtoanend-useroverasinglenetworkInexpensive,Simple,ScalableDeliveringbundledvoice,data,videoservicesPassiveOpticalNetwork(PON)Apoint-to-multipointopticalnetworkTwoprimarytypesofPONtechnologiesATMPONEPONPONTopologyEthernetPassiveOpticalNetworkEPONstartedtobestandardizedbyIEEE802.3ahEFMsince2001(2004Julydone)EthernetisaubiquitoustechnologyDeployedwidelyinLAN,MANandWANEthernetismoreattractivetoPONthanATMHighspeed-upto10Gigabit/sLowercostEasierinteroperabilityEPONArchitectureFeaturesofEPONAlldatapacketscarriedinEPONareencapsulatedinEthernetframesBroadcastinginthedownstreamdirectionfromtheOLTtoONUsSharingtheupstreamchannelcapacityamongONUs

Thatistheproblem!DownstreamUpstreamMulti-PointControlProtocolTheMulti-PointControlProtocol(MPCP)specifiesacontrolmechanismbetweenaMasterunitandSlavesunitsconnectedtoaPoint-to-Multi-Point(P2MP)segmenttoallowefficienttransmissionofdataMPCPisimplementedinMACControllayerMPCPusesfiveMACControlmessagesGATE,REPORT,REGISTER_REQ,REGISTER,andREGISTER_ACKMotivationMotivationAdynamicbandwidthallocationschemewithacreditmechanismwhichcansupportQoSserviceandreducepacketdelayDynamicBandwidthAllocationSchemeIPACTInterleavedPollingwithAdaptiveCycleTimeDBAMDynamicBandwidthAllocationwithMultipleServicesDBAwithQoSDynamicBandwidthAllocationwithQoSIPACTOperationStep(1/4)IPACTOperationStep(2/4)IPACTOperationStep(3/4)IPACTOperationStep(4/4)Definition(1)EFExpeditedForwarding，HighPriorityAFAssuredForwarding，MediumPriorityBEBestEffort，LowPriorityDefinition(2)

Themaximumbandwidthparameterofaspecific classoftrafficisdeterminedbytheSLAbetweentheenduserandserviceprovider

theamountofdataqueuedupinthebuffer

istherequestedbandwidthforclassctraffic

theestimationcreditWaitingTime&CycleTimeDBAMOperationDBAMCaseSLASiEF:20AF:30BE:50RequestRiEF:60AF:20BE:20CreditCiEF:70AF:25BE:25EF:20AF:25EF:20AF:25BE:55AssignBandwidth=100Definitions

Actualqueuesizewhentransmissionstart

FinallyguaranteebandwidthWaitingTime&CycleTimeDBAwithQoSOperation(1/2)DBAwithQoSOperation(2/2)DBAwithQoSCaseSLASiEF:20AF:30BE:50RequestRiEF:60AF:20BE:20CreditCiEF:70AF:25BE:25AssignBandwidth=100EF:20AF:20BE:20

ActualQueueRequestAiEF:65AF:30BE:25GiEF:20AF:20BE:20GiEF:20AF:25BE:25GiEF:50AF:25BE:25RequestRiEF:60AF:20BE:20DBAMGiEF:20AF:25BE:55SimulationModelEPON的系統頻寬1GbpsONU個數16封包大小64~1518Bytes佇列大小1Mbytes模擬時間1秒系統負載(NormalizedOfferLoad)0~2SLA比例EF-20%AF-30%BE-50%封包產生方式PoissonSimulatedResult(1)SimulatedResult(2)SimulatedResult(3)SimulatedResult(4)SimulatedResult(5)CreditConsideration

SimulationResult(1)SimulationResult(2)SimulationResult(3)C