在這篇論文中，我們提出了使用平行運作的不超前延遲線來建構最大延遲為ｄ的彈性延遲線。首先我們證明了對於一個固定條數的不超前延遲線，將到達的封包交付給哪一條不超前延遲線的最佳策略，就是選擇擁有最大的剩餘服務時間且維持先前先出順序的不超前延遲線。
在這樣的一個選擇策略下，我們證明了要完美的模擬彈性延遲線只需要⌈(d+1)⁄2⌉條不超前延遲線。我們也証明了若這樣的系統可以容許些微的封包丟失機率，則可以用Ｏ(√d)條不超前延遲線來建構之。

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