无线区域网路中自我相似交通流量之

無線區域網路中自我相似交通流量之

成因與效能評估

Theoriginandperformanceimpactofself-similartrafficforwirelesslocalareanetworks報告者：林文祺指導教授：柯開維博士OutlineBackgroundofSelf-SimilarityPropertiesofWLANTrafficEstimationofSelf-SimilarTrafficTheOriginofSelf-SimilarityinWLANImpactofSelf-SimilartoCSMA/CAperformanceImpactofSelf-SimilartoCSMA/CAperformancewithRTS/CTSBackgroundofSelf-Similarity(1/8)Self-SimilarityandFractalBackgroundofSelf-Similarity(2/8)StatisticsofSelf-SimilarityDefinitionofSelf-SimilarStochasticProcess:H:Hurstparameterorself-similarityparameterBackgroundofSelf-Similarity(3/8)Self-SimilarityofStatisticsDefinitionofSelf-SimilarStochasticSequence:Ex.BackgroundofSelf-Similarity(4/8)PropertiesofSelf-SimilarityLongrangedependenceSlowlydecayingvarianceHeavy-taileddistributionBackgroundofSelf-Similarity(5/8)Self-SimilarTrafficBackgroundofSelf-Similarity(6/8)

X(t)isaParetodistributionrandomprocesswithshapeparameterαandlocationparameterk.ParetoDistribution:BackgroundofSelf-Similarity(7/8)Variance-timePlot

R/SPlotBackgroundofSelf-Similarity(8/8)PropertiesofWLANTraffic(1/2)WLANtrafficTimeUnit=1SecTimeUnit=0.1SecTimeUnit=0.01SecBasic:1μSAggregation:1,0.1,0.01SecEnvironment:7NBPoissontrafficPropertiesofRealNetwork(2/2)

TimeUnit=0.01SecTimeUnit=0.1SecTimeUnit=1SecEstimationofSelf-SimilarTraffic(1/2)PacketsSequenceonWLANEstimationofSelf-SimilarTraffic(2/2)VariancePlot&R/SPlotSingleSourcewithoutCSMA/CATheOriginofSelf-SimilarTraffic(1/3)TheOriginofSelf-SimilarTraffic(2/3)VariancePlot&R/SPlotTheOriginofSelf-SimilarTraffic(3/3)VariancePlot&R/SPlotforWLANbasedonsinglePoissonTraffic.(Simulated)ImpactofSelf-SimilartoCSMA/CAperformance(1/7)MaximumthroughputTheinfluenceofnodesonSelf-SimilarTrafficandPoissonTrafficTheinfluenceofpacketlengthonSelf-SimilarTrafficandPoissonTrafficImpactofSelf-SimilartoCSMA/CAperformance(2/7)MaximumthroughputImpactofSelf-SimilartoCSMA/CAperformance(3/7)MaximumthroughputImpactofSelf-SimilartoCSMA/CAperformance(4/7)TheinfluenceofnodesonSelf-SimilarTrafficandPoissonTrafficImpactofSelf-SimilartoCSMA/CAperformance(5/7)TheinfluenceofnodesonSelf-SimilarTrafficandPoissonTrafficImpactofSelf-SimilartoCSMA/CAperformance(6/7)TheinfluenceofpacketlengthonSelf-SimilarTrafficandPoissonTrafficImpactofSelf-SimilartoCSMA/CAperformance(7/7)TheinfluenceofpacketlengthonSelf-SimilarTrafficandPoissionTrafficMaximumthroughputTheinfluenceofnodesonSelf-SimilarTrafficandPoissonTrafficTheinfluenceofpacketlengthonSelf-SimilarTrafficandPoissonTrafficImpactofSelf-SimilartoCSMA/CAperformancewithRTS/CTS(1/4)ImpactofSelf-SimilartoCSMA/CAperformancewithRTS/CTS(2/4)MaximumthroughputImpactofSelf-SimilartoCSMA/CAperformancewithRTS/CTS(3/4)TheinfluenceofnodesonSelf-SimilarTrafficandPoissonTrafficImpactofSelf-SimilartoCSMA/CAperformancewithRTS/CTS(4/4)TheinfluenceofpacketlengthonSelf-SimilarTrafficandPoissonTrafficConclusionWLANTrafficisSelf-Similarregular&Single)WLANThroughputatnode=5MaxWLANThroughputatnode<5Poisson>SSWLANThroughputatnode>5Poisson<SSImpactofPacketLengthRTS/CTSnotinfluencethecharacteristicofPoissonandSelf-SimilarityThanksforyoura