Summary: | 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.
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