IEEE 802.11/802.16無線網路的MAC機制為儘可能爭取傳輸機會，此機制於壅塞的網狀網路環境中將造成傳輸速率過高及非必要封包碰撞的問題，進而嚴重降低網路傳輸效能。

本篇論文的目的旨在改善無線網狀網路環境中，因IEEE 802.11/ 802.16本身的MAC機制所導致的效能低落問題。我們利用賽局理論中零和賽局以強化競爭方式並計算及應用合理傳輸機會(Transmission Opportunities)及傳輸時機(Transmission Timing)，再依此將傳輸速率調降至合理的數值以降低無效封包的傳輸率。同時，此傳輸機會及傳輸時機將作為路徑選擇的重要依據。末了，我們利用網路模擬器NS2 (Network Simulator ver. 2)驗證及評估本論文所提出之方法的效能。

The MAC mechanism of IEEE 802.11 and 802.16 competes as much transmission opportunities as possible. In a congested wireless mesh network, this greedy competition will result in inappropriate data rates and unintentional packet collision problems, and thus reduce network performance seriously.

The objective of this research is aimed to solve these two problems to enhance the performance of wireless mesh networks. We propose a zero-sum-game based contention-enhancement in MAC mechanism to estimate rational transmission opportunities and transmission timing dynamically. These estimations will then be used in reducing unsuitable packet data rates and selecting better routing paths. At last, we use NS2 (Network Simulator ver.2) to evaluate the system performance of our proposed methods.

[1] Saadawi, T. and Xu, S., "Does the IEEE 802.11 MAC protocol work well in multihop wireless adhoc networks?," IEEE Communications Magazine, Jun. 2001.
[2] IAN F. AKYILDIZ and XUDONG WANG, "A Survey on Wireless Mesh Networks," IEEE Radio Communications, September. 2005.
[3] Gyu Myoung Lee, Jin Seek Choi, "A survey of multipath routing for traffic engineering," http://vega.icu.ac.kr/~gmlee/research/papers/a%20survey%20of%20multipath%20routing.pdf, 2007/10/09 visited.
[4] Takeshi Murakami, lwao Sasase, and Masaki Bandai, "Split Multi-Path Routing Protocol with Load Balancing Policy (SMR-LB) to Improve TCP Performance in Mobile Ad Hoc Networks," 2005 IEEE 16th International Symposium on Personal, Indoor and Mobile Radio Communications, Volume 3, 11-14 Sept. 2005.
[5] Pei-Hsiang Hsiao and H. T. Kung, "Layout Design for Multiple Collocated Wireless Mesh Networks," Vehicular Technology Conference, 2004. VTC2004-Fall. 2004 IEEE 60th, Volume 5, 26-29 Sept. 2004.
[6] Hung-Yu Wei, Samrat Ganguly, Rauf Izmailov, and Zygmunt J. Haas, "Interference-Aware IEEE 802.16 WiMax Mesh Networks," Vehicular Technology Conference, 2005. VTC 2005-Spring. 2005 IEEE 61st, Volume 5, 30 May-1 June 2005.
[7] Xiaoqing Zhu and Bernd Girod, "A Distributed Algorithm for Congestion-Minimized Multi-Path Routing Over Ad-Hoc Networks," Multimedia and Expo, 2005. ICME 2005. IEEE International Conference on, 6-8 July 2005.
[8] Qiang Shen and Xuming Fang, "A Multi-metric AODV Routing in IEEE 802.11s," Communication Technology, 2006. ICCT '06. International Conference on, Nov. 2006.
[9] Nakjung Choi, Yongho Seok and Yanghee Choi, "Multi-Channel MAC Protocol for Mobile Ad Hoc Networks," Vehicular Technology Conference, 2003. VTC 2003-Fall. 2003 IEEE 58th, Volume 2, 6-9 Oct. 2003.
[10] Tzu-Jane Tsai, Hsueh-Wen Tseng, and Ai-Chun Pang, "A New MAC Protocol for Wi-Fi Mesh Networks," Advanced Information Networking and Applications, 2006. AINA 2006. 20th International Conference on, Volume 1, 18-20 April 2006.
[11] Ray-Guang Cheng, Cun-Yi Wang, Li-Hung Liao, and Jen-Shun Yang, "Ripple: a wireless token-passing protocol for multi-hop wireless mesh networks," Communications Letters, IEEE, Volume 10, Issue 2, Feb. 2006.
[12] Da-Ren Guo, Kuochen Wang, and Lung-Sheng Lee, "Efficient Spatial Reuse in Multi-Radio, Multi-Hop Wireless Mesh Networks," Vehicular Technology Conference, 2007. VTC2007-Spring. IEEE 65th, 22-25 April 2007.
[13] Mansoor Alicherry, Randeep Bhatia, and Li Erran Li, "Joint Channel Assignment and Routing for Throughput Optimization in Multiradio Wireless Mesh Networks," IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, VOL. 24, NO. 11, Nov. 2006.
[14] Martin J. Osborne; Ariel Rubinstein, "A Course in Game Theory," The MIT Press, 1994.
[15] The Network Simulator ns-2, http://www.isi.edu/nsnam/ns.