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研究生：	張緯康 Chang, Wei-Kang
論文名稱：	IEEE 802.11e 無線網路效能分析 Performance Analysis and Enhancement for IEEE 802.11e Wireless Networks
指導教授：	陳文字 Chen, Wen-Tzu
學位類別：	碩士 Master
系所名稱：	管理學院 - 電信管理研究所 Institute of Telecommunications Management
論文出版年：	2006
畢業學年度：	94
語文別：	英文
論文頁數：	45
中文關鍵詞：	無線網路
外文關鍵詞：	IEEE802.11e, QoS, IEEE802.11, EDCA, Wireless networks
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無線網路的發展無疑的對人類帶來了許多方便性，此種科技為我們提供了可以隨時隨地都可以與他人溝通以及計算的能力，無論是在辦公室、醫院、校園甚至是工廠之中，我們可以不用在為了要去哪裡找一條網路而困擾，而IEEE802.11無線區域網路正是目前最廣為使用的一種技術。
隨著IEEE802.11無線區域網路應用範疇的增加，人們希望即使是在行動中或是在辦公室或是在校園中都可以針對語音或是影像提供順暢的串流，因此IEEE 802.11 Task group E為了改善無線網路在QoS的能力而提出了IEEE 802.11e這個新的協定，這個新的協定將在MAC層提供QoS以幫助無線端能夠更有效率的傳送語音及影像資料，而其中被引進的新機制就稱之為EDCA(Enhanced Distributed Channel Access)，這是一個用來擴充原本IEEE 802.11協定中的DCF機制，它引進了四種存取類別(access category)，每種存取類別依據不同的參數如AIFS, CWs以及TXOPlimits來實現保證QoS的目的。
在本論文中，我們使用一個三維的馬可夫鏈模型進行IEEE 802.11e的吞吐量以及延遲的分析，為了驗證我們的模型，我們使用了NS-2網路模擬軟體證實了我們的分析是有效的，接著經由調整AIFS及CWs的參數，我們可以更瞭解此兩種參數對於效能的影響，並提出我們對於IEEE 802.11e標準在不同的QoS環境需求中，有一些參數上的建議。

The development of the wireless communication undoubtedly brings a lot of conveniences for humans. This kind of technology provides us the ability to compute and communicate to each other any time and any where such as in office, hospital, campus, and factory. We are no longer confused of trying to find out where the network cable is. However, IEEE 802.11 WLAN (Wireless Local Area Network) is the most popular used wireless communication technology to date.
With applications over IEEE 802.11 WLANs increasing, people want to receive the video, audio or any other usual data flow smoothly even when they are in the movement in the office or campus. So, Task group E of the IEEE 802.11 working group have proposed an extension to the IEEE 802.11 standard called IEEE 802.11e to improve the QoS capabilities provided on WLAN links. This new standard will provide QoS enhancements at the MAC layer that allow WLAN systems to efficiently stream audio and video data. A new access mechanism called EDCA (Enhanced Distributed Channel Access) is also proposed to extend the basic DCF mechanism used in the original 802.11 standard. Prioritized QoS is completed through the introduction of four access categories (AC). Each AC contends for channel access according to the different parameters such as different arbitration inter-frames spaces (AIFS) values, contention windows (CWmin and CWmax) and transmission opportunity (TXOP) limits.
In our study, we use a three dimensions Markov chain model to analyze the throughput and delay performance of IEEE 802.11e standard. In order to validate our model, we use NS-2 simulator to confirm our analysis results. By adjusting the AIFS and CWs values, we can understand more about the effect of both values and proposed our suggestions for IEEE 802.11e standard for different QoS environments.

CONTENTS...................................................................I
LIST OF FIGURES...........................................................III
LIST OF TABLES.............................................................V
Chapter 1   Introduction...................................................1
1	Introduction......................................................1
2	Motivation........................................................1
3	Objective	.........................................................1
4	Thesis Overview...................................................2
Chapter 2    Background and Related Research...............................3
1	A Brief of IEEE 802.11 standard...................................3
1.1	Distributed Coordination Function(DCF)............................3
1.2	Point Coordination Function (PCF).................................5
1.3	Carrier Sense Multiple Access with Collision Avoidance(CSMA/CA)...6
1.4	Interframe Space (IFS)............................................7
1.5	Exponential Backoff Procedure.....................................8
2	A Brief of IEEE 802.11e standard..................................9
2.1	Enhanced distributed channel access (EDCA)........................10
2.2	Arbitration InterFrame Space (AIFS[AC])...........................11
2.3	The minimum size of the contention window (CWmin).................11
2.4	Transmission Opportunity Limit (TXOPlimit)........................12
2.5	HCF controlled channel access (HCCA)..............................13
3	Related Research..................................................13
3.1	Throughput analysis for IEEE 802.11...............................13
3.2	Throughput analysis for IEEE 802.11e..............................14
Chapter 3    Performance analysis of the EDCA and the Proposed Mechanism...16
1	Proposed mechanism algorithm......................................16
2	Three Dimensions Discrete Time Markov Chain Model.................16
2.1	Transition Probabilities..........................................18
2.2	System Equations..................................................20
2.3	Throughput Analysis...............................................22
2.4	Delay Analysis....................................................23
Chapter 4    Simulation and Analysis Results...............................24
1	Simulation Environment............................................24
2	Validation of the Proposed Model..................................25
3	Throughput and Delay Analysis – Voice as principal...............27
4	Throughput and Delay Analysis – Video as principal...............34
5	Summary...........................................................41
Chapter 5    Conclusion and Future Work....................................43
Reference	..................................................................44

                                    

[1] IEEE Std 802.11-1999, “Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications,” 1999.
[2] IEEE 802.11e draft/D4.0, “Part 11: Wireless Medium Access Control (MAC) and Physical Layer (PHY) Specifications: Medium Access Control (MAC) Enhancements for Quality of Service (QoS),” Nov. 2002.
[3] Brian P. Crow, Indra Widjaja, Jeong Geun Kim, Prescott T. Sakai, “IEEE 802.11 Wireless Local Area Networks,” IEEE Communications Magazine, Sep. 1997. pp.116-126.
[4] Dajiang He, Charles Q. Shen, “Simulation Study of IEEE 802.11e EDCF,” Vehicular Technology Conference, Apr. 2003, pp. 685-689.
[5] E. Ziouva, T. Antonakopoulos, “CSMA / CA Performance under High Traffic Conditions: Throughput and Delay Analysis,” Computer Commun., Vol. 25, Feb. 2002, pp. 313-321.
[6] G. Bianchi, “IEEE 802.11-Saturation Throughput Analysis,” IEEE Commun. Lett., Vol.2, Dec. 1998, pp. 318-320.
[7] G. Bianchi, “Performance Analysis of the IEEE 802.11 Distributed Coordination Function,” IEEE Journal on Selected Areas in Communications, Vol. 18, No. 3, Mar. 2000, pp. 535-547.
[8] Hua Zhu, Imrich Chlamtac, “Performance Analysis for IEEE 802.11e EDCF Service Differentiation,” IEEE Transactions on Wireless Communications, Vol. 4, No. 4, Jul. 2005, pp. 1779-1788.
[9] Jeffrey W. Robinson, Tejinger S. Randhawa, “Saturation Throughput Analysis of IEEE 802.11e Enhanced Distributed Coordination Function,” IEEE Journal on Selected Areas in Communications, Vol.22, No.5, Jun. 2004, pp. 917-928.
[10] P. Chatzimisios, V. Vitsas, A. C. Boucouvalas, “Throughput and Delay Analysis of IEEE 802.11 Protocol,” in Proc. 5th IEEE Workshop Networked Appliances, Oct, 2003, pp. 168-174.
[11] Stefan Mangold, Sunghyun Choi, Guido R. Hiertz, Ole Klein, Bernhard Walke, “Analysis of IEEE 802.11e for QoS Support in Wireless LANs,” IEEE Wireless Communications, Vol. 10, No. 6, Dec. 2003, pp. 40-50.
[12] S. T. Sheu, T. F. Sheu, “A Bandwidth Allocation / Sharing / Extension Protocol for Multimedia over IEEE 802.11 ad hoc Wireless LANs,” IEEE J. Select. Areas. Commun., Vol. 19, Oct. 2001, pp. 2065-2080.
[13] X. Yang, “IEEE 802.11e wireless LAN for quality of service,” in Proc. IEEE Wireless Communications and Networking Conf., New Orleans, LA, Mar. 2003, pp. 1291–1296.
[14] Zhen-Ning Kong, Danny H. K. Tsang, Brahim Bensaou , Deyun Gao, “Performance Analysis of IEEE 802.11e Contention-Based Channel Access,” in IEEE Journal on Selected Areas in Communications, Vol. 22, No. 10, Dec. 2004, pp. 2095-2106.
[15] An IEEE 802.11e EDCA and CFB Simulation Model for NS-2, http://www.tkn.tu-berlin.de/research/802.11e_ns2/
[16] The Network Simulator NS-2, http://www.isi.edu/nsnam/ns/

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