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The interaction of congestion control and prioritized statistical multiplexing for real-time services (e.g., voice and video) in cell-based networks (e.g., B-ISDN based on ATM) with call blockings is studied. Focus on a bufferless mu-ltiplexer supporting real-time ON-OFF sources. Real-time source information is divided into two streams, low- and high-priority streams, in accordance with importance. Favored transport is given to high-priority stream resulting in s-ignificantly better QoS than unprioritized system. Two prioritization schemes are considered. In the first approach, independent channels of different QoS are used to transport low- and high-priority streams. In the second approach, a single channel is used in conjunction with a selective packet discarding pr-ocedure which means to limit packet loss to low-pritority stream. The effect of packet loss on quality is quantified by relating low- and high-priority pa-cket loss to signal-to-reconstruction-noise ratio (SNR). Both static and dyna-mic scenarios are studied. In the static scenario, the number of calls are fi-xed; while in the dynamic case, the number of calls are varying due to call r-andom arrivals and terminations. Firstly, the optimal allocation of source in-formation and channel capacity in the static scenario is found. Secondly, the dynamic allocation of source information and channel capacity are compared to the fixed allocation, and it is shown that the dynamic allocation could achie-ve much better SNR than the fixed allocation in many cases.
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