先前之研究發現在MANET中利用多重路徑繞線機制，可以減少因為路徑斷裂再次發起路徑找尋的機會，如此也就可以降低整體的繞線負擔以及封包傳送延遲時間。而透過多重路徑將資料封包分流，可以增加網路傳輸的效能。但是，目前尚未有特別針對無線應用網路的多重路徑繞線機制的提出，為了彌補這一部分的不足，並考慮到日漸普遍的無線應用網路的特質。本論文乃針對無線應用網路發展一套有效的多重路徑繞線機制。
因為無線應用網路的資料封包傳輸方向是以由網際網路閘道器下行的連結為主，這有別於MANET，傳輸的兩端節點皆是主動的一方，再加上閘道器擁有豐富路徑資訊，所以，我們機制的出發點是以發出需求的行動節點以及閘道器兩者，共同負責路徑的建立。而如何有效的去使用路徑快取，以抑制不必要的封包匯集到閘道器，減低網路的擁塞情形，並且透過閘道器的輔助，建立不重疊的多重路徑，是本研究的重點。最後，我們以模擬的方式驗證機制的效能並與其他方法比較之。

Multipath routing can reduce the effort of route discoveries, the overall routing overhead and the average end-to-end delay by providing alternative routes between communicating sources and destinations in the MANET. With multipath mechanism data traffic can be split into multiple routes to avoid congestion and to use network resources efficiently. Although there has been much research effort being devoted to the design of multipath routing mechanisms, for MANETs they are not tailored to in wireless access networks. In this thesis, we propose an on-demand multipath routing that can adapt to the wireless access network.
Unlike MANETs, in wireless access network, most traffic is imposed upon downlink channels from the gateway. In addition, the gateway has rich route information. In the thesis, we propose a multipath routing that relies on the collaboration between the gateway which perform the route selection scheme and the mobile node that initiate the route discovery operation. Our approach can restrain efficiently the control packet by utilizing the routing cache in the intermediate nodes. According to the gateway information, we then establish the node-disjoint multipath that can adapt to the dynamics of the network. Extensive simulations are performed to evaluate the performance of our mechanism. We also compare our scheme with the previous methods.

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