藉由分波多工技術，不同的波幅可以同時在一條光纖中傳輸。其中，每個波幅都可提供高達每秒數十億位元的頻寬。波幅路由器的使用，讓若干連結可以在互斥 的路徑中配置相同的波幅，因此提高了波幅的利用率。在沒有波幅轉換功能的分波多工網路中，系統必須在路徑上配置相同的波幅來建立連結。因此，若連結要求的路徑經過較多鏈結將比較不易配置到可用的波幅，而使得連線要求的阻斷率相對的提高。
本論文的目的在探討連結公平性的問題，此問題源自於來源節點至目的節點間的連結長度不同而導致的阻斷率失衡情況。能夠不受路徑長度的增加而增加。本論文提出一個適用於分波多工全光學網路架構的路由與波幅指定的策略，使得阻斷率較高的連結能夠獲得較多的光徑來降低連結失敗的機率。此外，我們也提出一個分析模式來計算網路中每個來源節點至目的節點間連結的阻斷率，並以此分析模式來找出阻斷率較高的連結，據此給予光徑。
此外，我們以模擬的結果來評估我們的分析模式的正確性，並且指出多路徑選擇策略在給予不同的網路參數時，例如：拓樸、路徑數量等等所能降低的阻斷率。而不同的路由與波幅指定策略所造成的影響也將以公平性的角度予以探討。

The vast bandwidth in fibers can be efficiently tapped by advanced WDM technology, by which several different wavelengths are simultaneously transmitted in an optical fiber and each carries traffic at several Gbps. The use of wavelength router in WDM networks provides topological dynamics to support high aggregate capacity by wavelength reuse at disjoint paths. Without wavelength conversion, a connection is set up by allocating the same wavelength of every link along the path. Consequently, longer connections require to win more times contending to use the same wavelength on each link, which results in a higher blocking probability for distant connection requests.
This thesis aims to solve the fairness issue, which arises from the imbalance of blocking probabilities with regard to connection-path length. We propose a strategy, which continues to allocate one more light-path for a source-destination(S-D) pair found to have a higher blocking probability than others. This strategy incorporates an analysis model which is proposed to compute the blocking probabilities for S-D pairs and to identify the S-D pairs with maximum blocking probability in the network.
The proposed strategy for fairness and the analysis model are verified through simulations. Results show that the analysis model is accurate if offered load is high, and underestimated if offered load is low; and that the strategy, compared with others, achieves better fairness even for different network parameters and topologies.

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