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Introduction to Queuing Theory and Traffic Modeling. Prof Nelson L. S. da Fonseca State University of Campinas, Brazil Trento, March 2004. Multimedia Networks. Quality of Service. “ Perception of the quality of the transfer of information expressed by quantitative metrics”
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Introduction to Queuing Theory and Traffic Modeling Prof Nelson L. S. da Fonseca State University of Campinas, Brazil Trento, March 2004
Quality of Service • “Perception of the quality of the transfer of information expressed by quantitative metrics” • Most commonly used QoS parameters: • Delay • Loss rate
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transmissio A propagation B processing queuing Delay
Transmission delay: R=bandwidth (bps) L=pkt size (bits) delay = L/R transmission A propagation B processing queuing Delay Propagation delay: • d = link length • s = propagation speed (~2x108 m/sec) • delay = d / s
Queuing Delay traffic intensity = La/R
Traffic • Flow of bytes. Telecom networks built to transport traffic;
Course Goals To understand the queuing phenomenon and relevance of traffic characteristic