Conference Paper

A Theory of QoS for Wireless

Dept. of Comput. Sci., Univ. of Illinois Urbana, Urbana, IL
DOI: 10.1109/INFCOM.2009.5061954 Conference: INFOCOM 2009, IEEE
Source: IEEE Xplore


Wireless networks are increasingly used to carry applications with QoS constraints. Two problems arise when dealing with traffic with QoS constraints. One is admission control, which consists of determining whether it is possible to fulfill the demands of a set of clients. The other is finding an optimal scheduling policy to meet the demands of all clients. In this paper, we propose a framework for jointly addressing three QoS criteria: delay, delivery ratio, and channel reliability. We analytically prove the necessary and sufficient condition for a set of clients to be feasible with respect to the above three criteria. We then establish an efficient algorithm for admission control to decide whether a set of clients is feasible. We further propose two scheduling policies and prove that they are feasibility optimal in the sense that they can meet the demands of every feasible set of clients. In addition, we show that these policies are easily implementable on the IEEE 802.11 mechanisms. We also present the results of simulation studies that appear to confirm the theoretical studies and suggest that the proposed policies outperform others tested under a variety of settings.

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    • "The packets not delivered by the end of the interval are dropped by the BS. The timely throughput measures the average number Fig. 2. Time model of a user for the timely throughput framework. of packets delivered before their deadlines, which handles the delay requirement and reliability performance jointly [34]. "

    Full-text · Article · Jan 2016 · IEEE Transactions on Wireless Communications
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    • "They are different in the assumption of the traffic. Some of them assume the traffic arrives at the beginning of the frame [11] [12], while others assume the arriving happens any time in the frame [14– 16]. They also differ in the introducing of channel fading [13], nonidentical delays [16], and so forth. "
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    • "It actually measures the mean probability that a user's packet is delivered before its transmission deadline, which evaluates the reliability performance under a delay constraint of τ time slots. According to the definition, the user timely throughput is given by [10] T "
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