在全光封包交換網路的主要問題裡，其中之一便是如何利用光交換機和光纖延遲線建造光佇列，以模擬暫存器的效果而達到暫存封包的目的。在這篇論文裡，我們考慮如何以光交換機及光纖延遲線建造出先進先出光佇列。論文[20]提出一個三級架構的建造方式，在其建造方式中使用了1個1×2光交換機和2k+1個2×2光交換機及總長為3•2k+2的光纖延遲線，以遞迴展開的方式建構出可貯存2^(k+1)-1個光封包的先進先出光佇列；然而在論文[20]中並沒有提出對於每一個光交換機的明確控制方式。而論文[51]則基於論文[20]之架構，提出對於每一個光交換機的明確控制方式，並證明在該控制方式之下，我們可以將該架構操作為一個容量為2^(k+1)-1的先進先出光佇列。
本篇論文主要的貢獻，是針對論文[20]的架構中每一條光纖延遲線的長度，對其選取方式提出一個猜想，並根據論文[51]中所提出的控制方式作相對應的修正，以使該網路元件可被操作為一個先進先出光佇列。而從電腦程式模擬的結果，我們也驗證了當光纖長度選取的方式滿足本論文所提出來的猜想時，該網路元件即可按照修正後的操作方式被操作為一個先進先出光佇列。

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