近年來，集中式控管的網路變得愈來愈熱門。這是由於有愈多人開始採用無線區域網路來打VoIP電話或者開視訊會議。因此，我們研究了提供語音、視訊和TCP檔案傳送服務的IEEE 802.11e集中式控管的網路。不同於許多研究人員只專注於行動站台的網路效能量標分析，我們同時考慮了行動台和AP。尤其，我們不僅考慮由多種行動台的上傳流量，並且考慮由多種AP的下載流量。我們考慮了四種情境。在情境三中，會有語音、視訊和TCP的服務同時存在。然而，在其他的情境中，我們考慮語音和TCP的服務同時存在。在情境一中，我們將到達語音AP的流量設為飽和。基於在相關文獻中的一個新穎的數學模型，我們可以找出在每通VoIP call的QoS都能符合的情形下的飽和點。而在情境二和四中，我們考慮到達語音AP的流量為非飽和。此外，我們研究了到達流量對於效能量標的影響在情境二和四中。我們考慮了兩種到達流量的模型，分別是Poisson和MMPP。其中，在其他文獻中，已經證實：數學模型的Poisson流量與模擬結果的CBR流量在我們的情境中，是恰巧穩合的。而MMPP的流量則是用來模擬真實網路中自我類似性的多媒體流量。我們有興趣的效能量標為企圖速率、碰撞速率、成功到達率、企圖機率、碰撞機率。結果顯示：到達流量的叢發特性將會影響效能量標。我們將分析語音和TCP服務的模型做進一步的推廣，用它來分析語音、視訊和TCP流量同時存在的情境三。藉由此推廣的分析，我們的數學模型將可實現上傳和下載成功到達率公平性的目標。

In recent years, the IEEE 802.11e infrastructure network has become popular, because more and more people utilize WLAN to have a VoIP call or a video conference. Therefore, we study the IEEE 802.11e infrastructure network with voice, video, and TCP traffic. Unlike many studies focusing on the mobile stations only, we take into account both mobile stations and AP. Specifically, we consider not only the uplink traffic from various stations but also the downlink traffic from various APs. We consider four scenarios. There are voice, video, and TCP services in the third scenario, whereas voice and TCP services exist in the other scenarios. There is a saturated voice AP in the first scenario. Based on a novel analytical model in the literature, we find the associated saturation point under the constraint that the QoS requirement of each call is satisfied. There is an unsaturated voice AP in the second and four scenarios. We study the effect of packet traffic models on the performance measures in the second and four scenarios. The packet arrival traffic models considered are Poisson and MMPP. Moreover, in the literature, Poisson traffic in an analytical model has been shown as a good approximation for CBR traffic in simulation run and MMPP traffic is used to emulate the self-similar multimedia traffic in real networks. The performance measures of interest are attempt rate, collision rate, throughput, attempt probability, and collision probability. It is shown that the burstiness in packet arrival process does affect the performance measures. We also extend the associated analytical model to study the third scenario with voice, video, and TCP traffic. With extensive numerical experiments, it is shown that the fairness in throughput between the uplink and downlink voice traffic can be achieved.

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