為了解決擁擠網路中單一路徑可能無法滿足Request的問題，使用Multipath routing以分散對各路徑的頻寬要求是相當常見的做法，這個方法尤其常被使用在基於SONET系統的乙太網路中。然而使用多條路徑的路由將因為彼此之間的differential delay而對接收端產生較大的負擔，因此如何在使用多條路徑傳輸的同時，控制其各路徑的differential delay在一定限制下，也是相當重要的課題。在本篇論文中，我們提出多個注重於最小化differential delay與path distance的Multipath Routing演算法，並研究其在不同環境下的執行成效與速度。

While single routing path can hardly satisfy requests in a heavy loading network, it is common to use multipath routing to split the requested bandwidth into several smaller ones, especially in SONET-based ethernet. However, using multipath routing will generate "differential delay", which will cause additional loading for the memory of the receiver. As a result, how to constrain differential delay below a specific bound become a serious issue while using multipath routing. In this paper, we present several multipath routing algorithms, which can lower both differential delay and routing path distance, and the simulation result indicate these algorithms can all improve the network efficiency.

第一章Introduction…………1
第二章Related Work…………2
第三章The Proposed Algorithms…………5
A.Definition：…………5
B.Yen Branch Algorithm：…………6
C.Minimizing Differential Delay Inter-Reference Algorithm：…………8
D.Frame-select Algorithm：…………11
E.Combine with Dijkstra’s Algorithm：…………13
第四章Simulation…………15
A.Testbed：…………16
B.測量各演算法對獨立網路請求的表現實驗：…………16
C.測量各演算法運行時整體網路的表現實驗：…………20
第五章Conclusion…………26

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