高速信元交換結(jié)構(gòu)性能分析與調(diào)度算法研究.pdf

1、中國科學(xué)技術(shù)大學(xué)博士學(xué)位論文高速信元交換結(jié)構(gòu)性能分析與調(diào)度算法研究姓名：戴禮森申請學(xué)位級別：博士專業(yè)：信息與通信工程指導(dǎo)教師：李津生1999.11.1!塑型蘭墊查叁堂豎!：堡墨壘呈蘭!堡壘￡三ABSTRACTTheun口recedentedtrafficgrowthintheInteracthasdemandedmorebandwidthForthepastfewyearsgreatprogresshasbeenmadeinfibero

2、pticaltransmissiontechnologyThetransmissionratehasbeenincreasingatthespeedof100timesevery10yearsAskeyelements，switchesandroutersshouldadapttotherapidincreaseinbandwidthandsupporthighspeedswitchingHowevertraditionalswitch

3、esandroutersemployoutputqueueing，andforthispureoutput—queueingschemetowork，thespeedoftheswitchingfabricandOHtputbuffermemoryisrequiredtobeNtimestheinputlinespeedwhereNisthenumberofinputlinesAsIinespeedsincreasetotheGb／sr

4、angeandasroutersandswitcheshavemoreinputports，therequiredfabricspeedbecomesinfeasibleMoreattentionshavebeenpaidtotheinputqueueingorcombinedinputandoutputqueueing11011blockingcell—basedfabricforitshighspeedandsimplicityto

5、implementMoreover，inputqueueingfabricinsomehigh。speedroutersisreplacingthesharedbusInthisschemetheheadoflineblockinginthetraditionalinputqueueingfabriccanbeeliminatedandthethroughputcanbeincreasedto100％byusingsomekindsof

6、schedulingalgorithmsOntheotherhand，withtheincreasingofthesizeoftheIntemet，especiallymoreandmoremultimediaapplicationsintroducedintotheInternetitisdesirablethatswitchesandroutersprovidevariousqualityofservice(QoS)guarante

7、esinadditiontoprovidinghighbandwidthInthetraditionalroutersandswitchesthatemployoutputqueueing，whenpacketsarriveataninputport，high—speedswitchingfabricimmediatelytransfersthemtothecorrectoutputportDataarcthenstoredinoutp

8、utqueues，andoutputscheduleraccordingtoeachapplication，determinestheexacttimewhenapacketwilldepartfromtheport，whichprovidesvariousqualityofservice(QoS)featuressuchasdelaybandwidthandfairnessguaranteesIfinputqueueingfabric

9、isusedwhenmorethanonepacketcontendsforthesameOHtputonlyoneistransferredtotheoutOutandtheotherswillbetemporarilydelayedintheinputqueuesThisisbecausethefabrichasthesamespeedasthatofinputandOHtputlinesandonlyonepacketisadmi

10、ttedateverycelltimeTheseadditionalinput—sidequeueingdelaymakesitmoredifficulttoprovideQoSguaranteesthanintheoutputqueueingswitchSo，moreandmoreresearchactivitieshavefocusedonthestudyoftheadditionalinput—sidequeueingdelayo

11、nQoSundervariousconditionsandthedesigningofschedulingalgorithms，whichprovideQoSguaranteesInthisthesisweanalyzeandstudythehighspeedcellbasedswitchingfabricandsomeschedulingalgorithmssystematicallyanddeeplyonthebackgroundo

12、fthenationalresearchprojectweunderake“Ttledevelopmentofhighspeedrouter”Firstlywedescribesystemmodelandtramcandstudytheperformanceofcombinedinputandoutputqueueingnonblockingswitchingfabric，whichisanderqueuelOSStransfersch

13、emeThroughnumericalanalysisandsimulationwestudytheeffectsofunifoITUandnonuniformtra銜conthecelllOSSandqueueingdelaydistributionsofthefabricInaddition，adynamicbuffersharingalgorithmtolessencelllOSSisproposedInordertoelimin

14、ateHOLblockingininputqueueingfabricwestudyandcompareafewofwindowaccessschemesproposedinIiteraturebymeansofcomputersimulationAnewdoublecrossbarinputqueuedfabricispresentedtolessenHOLblockingltisshownthatthethl’oughputofth

15、efabricweproposeisbetterthanthatofthetraditionalFIFOfabric，whichreachesto76％AndjtlseasiertoimplementthaninputexpansionschemeAlsowequantitativelyevaluatesevelalschedulingalgorithmsforvirtualoutputqueueing(VOQ)bysimulation

16、InparticularwecomparetheperformanceandimplementcomplexityofsomeschedulingalgorithmsproposedpreviouslyinliteratureTheresultsarehelpfultothefabricdesignItispracticallysignificant，atthesametimechallenging，tealizeQoSguarante

17、eininputqueueingfabricWestudyandcompareseveralweightsthatenableprovisionofvariousOoSguaranteesInaninput‘queueingswitchwithnospeedupbyusingavariationofstablemarriagematchingalgorithm，alsoamodificationisproposedAmodifiediS