000031957 001__ 31957
000031957 005__ 20190509131911.0
000031957 0247_ $$2doi$$a10.5075/epfl-thesis-1479
000031957 02471 $$2nebis$$a1625822
000031957 037__ $$aTHESIS
000031957 041__ $$afre
000031957 088__ $$a1479
000031957 245__ $$aModélisation markovienne du trafic dans les réseaux de communication
000031957 269__ $$a1996
000031957 260__ $$bEPFL$$c1996$$aLausanne
000031957 300__ $$a202
000031957 336__ $$aTheses
000031957 520__ $$aThe principal question we address in this work is the following: "Is Markov modelling appropriate to analyse data networks?". We will conclude that it is. The motivation for this question comes from the work of a research team at Bellcore who argue that the models used in teletraffic engineering are questionnable. Their argument is based on long measurements performed on their local network. Their results, with the major conclusion that the traffic is self-similar, have shaken the teletraffic community. After having exposed the principal characteristics of the Markovian model, we analyse measurements done on the EPFL network and on the Bellcore network. The results of the analysis lead us to suspect the suitability of Markovian models. Therefore, we study the interworking unit Ethernet/DQDB considering a network totally loaded. No hypothesis is made for the traffic profile, yet the study leads to strong conclusions and we therefore try to understand the queue behavior with the spectral analysis in order to better characterize the data traffic. The next step consists of reproducing the self-similarity observed in the data traffic with modulated Markov chains. Here, Courtois's theory of decomposability is used. We have shown that it is possible to reproduce self-similarity on a finite timescale, but that the number of parameters needed to manipulate in the modulated Markov remains large. In the next step, we propose a technique to reduce them drastically. A method of finding a Markov modulated chain as a function of the expectation, the local Hurst parameter and the domain where the process exhibits self-similarity has been developed. Finally, we analyse the statistical multiplexing in a new ATM architecture by comparing the multiplexing of VBR sources (with a modulated Markovian chains) on a CBR and on a VBR connection, using the above techniques.
000031957 6531_ $$aMarkov model
000031957 6531_ $$aCommunication network
000031957 6531_ $$aTraffic modelling
000031957 700__ $$aRobert, Stephan
000031957 720_2 $$aLe Boudec, Jean Yves$$edir.$$g105633$$0241098
000031957 8564_ $$uhttps://infoscience.epfl.ch/record/31957/files/EPFL_TH1479.pdf$$zTexte intégral / Full text$$s1461620$$yTexte intégral / Full text
000031957 909C0 $$xU10427$$0252453$$pLCA2
000031957 909CO $$pDOI$$pIC$$ooai:infoscience.tind.io:31957$$qDOI2$$qGLOBAL_SET$$pthesis
000031957 918__ $$bSSC
000031957 919__ $$aLCA2
000031957 920__ $$b1996
000031957 970__ $$a1479/THESES
000031957 973__ $$sPUBLISHED$$aEPFL
000031957 980__ $$aTHESIS