研究顯示機會路由應用於具遺失通道的無線網狀網路環境可有效提升網路吞吐量。不同於傳統的路由機制其封包之傳輸僅經由既定路徑之節點來轉發，機會路由技術允許多個收聽到封包的節點形成一轉發集，集合中之成員皆有機會實際參與該封包之轉發。現有機會路由協定通常由傳送端主導實際轉發節點之選擇，而忽略轉發集成員當前之負載。本論文提出一考慮轉發集成員負載之機會路由機制。具體來說，除了考量封包遞送機率之外，一傳送封包之可能轉發集僅能包含彼此在傳輸範圍覆蓋的無線節點。搭配有效的佇列管理機制，所提方案將使得從一封包傳送之轉發集脫穎而出的實際轉發節點係最早為該封包轉送取得無線通道之節點。因此，無線網狀網路中有效率和支援負載平衡之機會路由當可實現。數值分析結果顯示所提方法相較於傳統路由機制可達較高之封包遞送率。整體來看，所提機制不僅簡單、效率高，而且符合IEEE802.11s的MAC協議。

Opportunistic routing has been shown to achieve the high throughput of the wireless mesh network with lossy channels. Different from traditional routing mechanisms in which a transmitting packet is only forwarded by the node along with the deterministic path, the opportunistic routing technique allows multiple nodes hearing the packet to form the forwarder set containing promising candidates for the packet forwarding. Existing opportunistic routing protocols typically choose among forwarding candidates based on the decision made from the transmitter disregarding the current loads in candidates. In this paper, the opportunistic routing mechanism with considering race among forwarders is proposed. Specifically, in addition to the consideration of delivery probability, a candidate of the forwarder set for a given transmitter is restricted to those wireless nodes whose transmission range covers one another. Augmented with the novel queue management, our proposal makes the true forwarder picked from the forward set of a given transmitting packet being the one who gains access to wireless channel for the packet before others do. Therefore, the efficient and load-balanced opportunistic routing for wireless mesh networks can be achieved. Numerical results show that the proposed method compared to the traditional routing methodology can achieve the high packet delivery ratio. Overall, the proposed scheme is simple, efficient, and compliant to the IEEE 802.11s MAC protocol.

中文摘要 i
Abstract ii
目次 iii
圖目次 iv
表目次 v
1、緒論 1
1.1、研究背景 1
1.2、研究動機與目的 3
1.3、論文組織與架構 4
2、相關研究 5
2.1、IEEE802.11s 簡介 5
2.2、ExOR機制 9
2.3、其他相關路由機制 11
2.3.1、COPE機制 11
2.3.2、MORE機制 13
2.3.3、EMORE機制 15
2.3.4、CORE機制 16
3、考量轉送節點間競賽之無線網狀網路機會路由機制 18
3.1、實例說明 19
3.2、系統模型 22
3.3、演算法 23
3.4、IEEE802.11s機會路由之實現 25
4、數值分析 37
5、結論及未來展望 39
參考文獻 40

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