Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/19890
標題: IEEE 802.11分散式協調功能的效能改善之研究
The Study on the Performance Improvement of IEEE 802.11 Distributed Coordination Function
作者: 郭昭佑
Kuo, Chao-Yu
關鍵字: IEEE 802.11分散式協調功能
Pao-Ta Yu
廣播
二元指數後退演算法
Shyan-Ming Yuan
Tung-Shou Chen
Tsan-Pin Wang
出版社: 資訊科學與工程學系所
引用: [1] Raymond G. Ayoub, “Paolo Ruffini''s contributions to the quintic,” Archive for History of Exact Sciences, vol 23, no. 3, pp. 253-277, September 1980. [2] Giuseppe Bianchi, “Performance analysis of the IEEE 802.11 distributed coordination function,” IEEE Journal on Selected Areas in Communications, vol. 18, no. 3, pp. 535-547, March 2000. [3] Giuseppe Bianchi and Ilenia Tinnirello, “Kalman Filter Estimation of the Number of Competing Terminals in an IEEE 802.11 Network,” Proc. Infocom 2003, vol. 2, pp. 844-852, Mar. 2003. [4] Giuseppe Bianchi and Ilenia Tinnirello, “Remarks on IEEE 802.11 DCF performance analysis,” IEEE Communications Letters, Vol. 9, No. 8, pp. 765-767, August 2005. [5] Luciano Bononi, Marco Conti and Enrico Gregori, “Runtime Optimization of IEEE 802.11 Wireless LANs Performance,” IEEE Transactions on Parallel and Distributed Systems, vol. 14, no. 12, pp. 1-15, December 2003. [6] Raffaele Bruno, Marco Conti and Enrico Gregori, “A simple protocol for the dynamic tuning of the backoff mechanism in IEEE 802.11 networks,” Computer Networks, vol. 37, issue: 1, pp. 33-44, September 2001. [7] Raffaele Bruno, Marco Conti and Enrico Gregori, “Optimization of Efficiency and Energy Consumption in p-Persistent CSMA-Based Wireless LANs,” IEEE Transactions on Mobile Computing, vol. 1, no. 1, pp. 10-31, January-March 2002. [8] Frederico Cali, Marco Conti and Enrico Gregori, “Dynamic tuning of the IEEE 802.11 protocol to achieve a theoretical throughput limit,” IEEE/ACM Transactions on Networking, vol. 8, no. 6, pp. 785-799, December 2000. [9] Frederico Cali, Marco Conti and Enrico Gregori, “IEEE 802.11 Protocol: Design and Performance Evaluation of an Adaptive Backoff Mechanism,” IEEE Journal on Selected Areas in Communications, vol. 18, no. 9, pp. 1774-1786, September 2000. [10] Yassine Chetoui and Nizar Bouabdallah, “Adjustment mechanism for the IEEE 802.11 contention window: An efficient bandwidth sharing scheme,” Computer Communications, vol. 30, issue: 13, pp. 2686-2695, September 26, 2007. [11] IEEE Computer Society Committee LAN MAN Standards Committee, Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications. ANSI/IEEE Std. 802.11, 1999 Edition. The Institute of Electrical and Electronic Engineers. [12] Chuan Heng Foh and Juki Wirawan Tantra, “Comments on IEEE 802.11 Saturation Throughput Analysis with Freezing of Backoff Counters.” IEEE Communications Letters, vol. 9, no. 2. pp. 130-132, February 2005. [13] Chunyu Hu, Hwangnam Kim and Jennifer C. Hou, “Short-term non-uniform access in IEEE 802.11-compliant WLANs: A study on its impact on the saturation performance,” Computer Networks, vol. 52, pp. 61-76, 2008. [14] Jiwoong Jeong, Sunghyun Choi and Chong-kwon Kim, “Achieving weighted fairness between uplink and downlink in IEEE 802.11 DCF-based WLANs,” in Proc. IEEE QShine'05, Aug. 2005 [15] Byung-Jae Kwak, Nah-Oak Song and Leonard E. Miller, “Performance analysis of exponential backoff,” IEEE/ACM Transactions on Networking, vol. 13, no. 2, pp. 343-355, April 2005. [16] Younggoo Kwon, Yuguang Fang and Haniph Latchman, “A Novel MAC Protocol with Fast Collision Resolution for Wireless LANs,” Proceedings of the IEEE INFOCOM''03, vol. 2, pp. 853-862, 2003. [17] Tsung-Han Lee, Alan Marshall and Bosheng Zhou, “An Optimization Scheme for Energy Efficient Ad-hoc Wireless Networks Operating in Error-prone Channel Conditions,” Proceedings of the World Congress on Engineering 2009, vol. 1, WCE 2009, July 1 - 3, 2009, London, U.K. [18] Xiaomin Ma and Xianbo Chen “Performance Analysis of IEEE 802.11 Broadcast Scheme in Ad Hoc Wireless LANs,” IEEE Transactions on Vehicular Technology, vol. 57, no. 6, November 2008. [19] M.Ajmone Marsana, G. Tariccoa, G. Roncaroloa and G. Taglientea, “Simulation of three MAC protocols for intelligent highway packet radio networks,” Computer Communications, vol. 19, no. 12, pp. 943-953, Oct. 1996. [20] Hadi Minooei and Hassan Nojumi, “Performance evaluation of a new backoff method for IEEE 802.11,” Computer Communications, vol. 30, issue: 18, pp. 3698-3704, December 10, 2007. [21] Hamed Mohsenian Rad, Jianwei Huang, Mung Chiang and Vincent W.S. Wong, “Utility-Optimal Random Access without Message Passing,” IEEE Transactions on Wireless Communications, vol. 8, issue: 3, pp. 1073-1079, March 2009. [22] Network Simulator [Online]. Available: http://www.isi.edu/nsnam/ns/. [23] Ken Tang and Mario Gerla, “MAC layer broadcast support in 802.11 wireless networks,” in Proc. IEEE MILCOM, 2000, pp. 544-548. [24] Alberto Lopez Toledo, Tom Vercauteren, Xiaodong Wang, “Adaptive Optimization of IEEE 802.11 DCF Based on Bayesian Estimation of the Number of Competing Terminals, ” IEEE Transactions on Mobile Computing, vol. 5, no. 9, pp. 1283-1296, Sept. 2006 [25] Zhe Wang and Mahbub Hassan, “The Throughput-Reliability Tradeoff in 802.11-Based Vehicular Safety Communications,” 6th Annual Consumer Communications and Networking Conference (CCNC 2009), pp. 1-5, 10-13 Jan. 2009. [26] Li Yun, Long Ke-Ping, Zhao Wel-Liang and Chen Qian-Bin, “A novel random backoff algorithm to enhance the performance of IEEE 802.11 DCF,” Wireless Personal Communications, Vol. 36, No. 1, pp. 29-44, January 2006. [27] Jing Zhu and Sumit Roy, “MAC for dedicated short range communications in intelligent transport system,” IEEE Communications Magazine, vol. 41, no. 12, pp. 60-67, Dec. 2003.
摘要: 在IEEE 802.11的效能上,Backoff程序扮演非常重要的角色,尤其是對吞吐量(Throughput)和碰撞機率(Collision)效能的影響,舉凡大部份的文獻,都以此二項為效能改善的指標,而本研究主要針對Backoff程序的改善,提出分析和NS2 (Network Simulator 2)模擬,以驗證分析和模擬是一致的。 目前在IEEE 802.11廣播效能的研究上,都是假設傳輸訊框成功所花費的時間等於傳輸訊框失敗的時間。並沒有考量EIFS (Extended InterFrame Space)時間的影響,以至於分析與模擬的結果發生不一致的現象。本篇考慮EIFS時間的影響,修正Hu所提出的模型,利用吞吐量(Throughput)和訊息可靠性(Message Reliability)為效能指標。模擬實驗顯示我們提出的方法與模擬的結果最為接近,代表我們的分析的方法較接近於實際的情況。 針對改善IEEE 802.11的論文不計其數,但有考量到EIFS影響的論文,就作者的記憶,還未有相關論文出現,本論文考量到EIFS (Extended InterFrame Space)的影響,透過理論分析,求解最大吞吐量(Maximum Throughput)的問題,提出一個更接近最佳解的分析和演算法,有別於其它論文是採用數值方法去逼近最佳解,本篇以二元三次方程式即可獲得更接近最佳解的演算法,另外透過對本篇演算法的特性,分析出CFP (Backoff Counter Consecutive Freeze Process)的影響是可以忽略,甚至可以不去考慮。 另外在IEEE 802.11的DCF (Distributed Coordination Function)模式下,CSMA/CA (Carrier Sense Multiple Access/Collision Avoidance)是使用二元指數後退演算法來避免封包碰撞的發生。至於二元指數後退演算法是使用均勻分布的機率模型,來選取可能的後退值,而本研究提出一個創新的二元指數後退演算法,即是在二元指數後退演算法中使用二項式分配取代均勻分布的機率模型,來選取可能的後退值,並且透過使用NS2模擬,驗證二項式分配的方法可以獲得可觀的效能改善。
The backoff procedure plays a very important role in IEEE 802.11 WLANs. In particular, both throughput and collision are not only widely affected by the backoff procedure, but also act as two of the most important performance indicators for performance improvement in most of the literatures. In this thesis, we focus on the improvement of backoff procedure that uses proposed analytical model and NS2 (network simulator 2) simulations to confirm the accuracy of proposed theoretical analysis. The current researches on the performance of IEEE 802.11 broadcast have all assumed that the time taken for a successful frame transmission is the same as the time taken for an unsuccessful frame transmission. However, none of these studies have considered the effects of an extended interframe space (EIFS). Therefore, their analysis and simulation results are not consistent with each other. Based on this observation, we have taken the effects of EIFS into consideration and modified the model proposed by Hu. We use throughput and message reliability as the performance benchmark in our simulation to show that our proposed method yields results that are closest to the simulation results. From the definition of throughput, we have taken such observation further to perform theoretical analyses to provide a solution to the maximum throughput problem for the IEEE 802.11 distributed coordination function (DCF), and an algorithm using a binary cubic equation to obtain a much closer approximation of the optimal solution than previous algorithms. Moreover, by studying and analyzing the characteristics of the proposed algorithm, we found that the effects of backoff counter consecutive freeze process (CFP) could be neglected or even disregarded. From the simulation result, we not only showed that the proposed theoretical analysis complied with the simulated results, but also verified that the proposed approach outperformed others in achieving a much closer approximation to the optimal solution. Apart from EIFS, the carrier sense multiple access/collision avoidance (CSMA/CA) in IEEE 802.11 DCF uses binary exponential backoff (BEB) algorithm to select a random backoff number from a uniform probability distribution to avoid the problem of packet collision. In this thesis, we present a novel backoff algorithm that uses a binominal distribution rather than a uniform distribution to determine the backoff value. In our simulations, the results have shown that the proposed algorithm outperforms the original IEEE 802.11 DCF algorithm.
URI: http://hdl.handle.net/11455/19890
Appears in Collections:資訊科學與工程學系所

文件中的檔案:

取得全文請前往華藝線上圖書館



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.