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8Chapter
QoS: Quality-of-Service
e introduction of the Internet as a communication infrastructure has exposed the
need for quality-of-service. QoS is much more pressing in real-time traffic (services)
such as voice over IP, IPTV, video streaming, and video-conferencing. e term
“quality-of-service” is used very loosely in telecommunications to refer to signal
qualities that determine the performance of a communication system. Quantities
such as signal-to-noise ratio (SNR), bit error rate (BER), and packet (frame or cell)
loss ratio are involved. In addition, QoS is some measure of the average transfer rate
of information between the sender ...