無線網狀區域網路是由一些支援網狀服務(Mesh service)的節點所組成的通訊網路。在IEEE802.11s草案中，除了導入網狀網路架構外，亦加入以預約為基礎的存取機制，稱為MDA(Mesh deterministic access)。MDA能讓節點以較少的競爭與碰撞來進行媒體的存取。而在之前的研究中，有提出可以讓MDA運行在多通道環境下的機制，稱之為Multi-channel MDA(MMDA)。而MMDA相較與原本的MDA確實有效提升系統的效能。之後亦有研究提出當MMDA在高負載的情況下，各通道之間的傳輸區間(Data Transmission Period)都已經被預約飽和時，則可以動態的調整競爭區間，使得傳輸區間長度變長，來預約到更多的MDAOP(Mesh deterministic access transmission opportunities)，以提高系統的效能。
在多點跳躍的網路環境下，各個網狀節點的佇列皆是以先來先服務的方式在傳遞資料。因此高Hop-count的資料在轉送的過程中，往往是位於佇列較後方的位置。所以在系統負載較重時，高Hop-count資料傳送的機會就較少，因此被系統丟棄的機率就會相對提高。加上高Hop-count的資料再重新傳送時的成本也會比低Hop-count要來的高。這樣就會造成網路資源的浪費及不公平。
為了解決上述的問題，本論文在MMDA網狀網路的架構下，提出了一個動態調整資料在佇列的排序方式。本論文考慮了資料本身的Time-to-live(TTL)以及MeshRetryTimeout來做為調整的因素。使得高Hop-count的資料在佇列中能有較高的傳送優先權，以減少資料被丟棄的機會，來提升高Hop-count資料的傳輸效能。相對的減少一些低Hop-count的資料產能，以取得系統在各個Hop-count之間在產能上的平衡。

A wireless mesh LAN is a communications network made up of radio nodes that support Mesh service. In IEEE 802.11s draft, not only the Mesh network topology be introduced, but also a new reservation based MAC access scheme, MDA, be introduced. Nodes that support MDA can access wireless medium with lower collision probability. In a previous study, it was suggested so that MDA can operate on multi-channel environment. Compared with the MDA, MMDA does effectively enhance the system performance. In addition, there has a research study on MMDA in high loading situation. The data transmission period has been reserved to the saturation, and it can dynamically allocate Contention Period ratio to increase date Transmission Period. So it helps to reserved more MDAOP to improve system performance.
However, in multi-hop network environment, each mesh nodes transmission data are first-in-first-out sorting mechanism. Thus, when the high hop-count data is in the forwarding process, it’s also arranged in a queue behind the position. When the network load becomes heavy, high hop-count of transmission opportunities will be reduced. Hence, discard probability will improve. Besides, the high hop-count data re-transmission cost is also higher than the low hop-count. This result will cause the waste of network resources and unfairness. In order to solve the above problems, we propose a dynamic adjustment of the sorting queue. The method considers data Time-to-live (TTL), and MeshRetryTimeout to do the adjustment factors. This thesis hopes to increase the transmission performance of high hop-count to achieve balance of the network system.

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