在這一篇論文中，我們針對Carry-Over Round Robin(CORR)排程法的一些缺陷進行改進。和CORR比較起來，修正後的方法降低了實作的複雜度，在分配頻寬上也更加的公平，在網路的延遲方面則是互有高低。整體而言，改進後的方法可說是精簡了CORR的演算流程，CORR使用了某些設計來維持訊框的最大值，我們則證明了訊框最大值其實是可以不存在的，移除這些維持最大值的多餘步驟反而可讓排程法分配頻寬更加的公平。除此之外，我們也注意到排程法和Shaper各自獨立運作時，網路頻寬使用效率較低的問題，我們利用CORR原來將訊框分為Major Cycle及Minor Cycle的構想，設計將排程法內的一些資訊適時的回饋給Shaper，然後在Minor Cycle中處理由Shaper傳輸過來的細胞，如此一來可望能在不影響排程法與Shaper的基本效能下，成功的提高網路頻寬使用率。

In this thesis, we propose a cell scheduling mechanism to overcome some drawback of Carry-Over Round Robin (CORR) algorithm. Compare with CORR, the modified scheme reduces complexity of implementation and allocates bandwidth more fairly. In general, it simplifies CORR algorithm, which applies some design to maintain the maximum frame size. We prove that the maximum frame size is not necessary for deriving end-to-end delay. We also show that it results in fair distribution of bandwidth.
As long as the schedulers and traffic shapers work independently, significant underutilization is expected. In order to solve this problem, we borrow the concept of CORR which divides each allocation cycle into two subcycles—a major cycle and a minor cycle. By designing some information feedback to shapers, schedulers can transmit more cells in minor cycles. Hence we can improve bandwidth utilization successfully.

內容目錄
中文摘要
英文摘要
目錄
圖目錄


第一章 簡介 1

第二章 排程法概論 3
2.1 排程法簡介及研究動機 3
2.2 ATM網路簡介 6
2.3 CORR排程法 7
2.4 CORR的優缺點 12

第三章 我們提出的排程方法 14
3.1 修正CORR 14
3.2 排程法結合Shaper 18

第四章 數學分析 21
4.1 Fairness Property 21
4.2 Delay in single node 24
4.3 Delay in multinode 28
4.4 Comparison with CORR 33

第五章 模擬結果 35

第六章 總結 39

參考文獻 40

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