隨著寬頻網路的普及，網路上流傳的檔案越來越大，下載人數也大幅增加，傳統主從式架構的檔案下載方式，伺服器端難以負荷如此龐大的儲存空間與頻寬，造成近年來，點對點網路架構已經成為大型檔案下載的主流方式。此外，隨著流傳的檔案數量增加，多檔案同時下載也成為趨勢；因此，如何增進點對點網路中多檔下載之效能將會是主要課題。在本論文中，我們將排程的概念應用在點對點網路的多檔案下載中，根據檔案的重要性、即時下載表現、完成進度以及等待時間來衡量檔案的優先權，再根據優先權將檔案排入佇列中，並依照佇列順序來啟動或暫停檔案，如此一來，在進行多檔下載時，我們可以避開表現不好的檔案，而優先下載有較高效率的檔案，此外，我們也避免傳輸重複的檔案，並且增加頻寬的使用率，試圖在有限的頻寬下取得更多的下載量，經過實驗驗證，我們的方法可確實地增進頻寬使用率。

As the available bandwidth for individual user increases, more and more people get used to download files from the Internet. Also, as the file sizes become larger and larger, it is usually challenging for a server to serve a large number of clients in a conventional client-server scheme. Thus, the Peer-to-Peer (P2P) architecture has become a popular way for file exchanging nowadays. Since each user may download more than one file at a time, how the efficiency of P2P multi-file downloading can be improved is a critical issue. In this work, scheduling techniques are utilized for P2P multi-file downloading. Specifically, the priorities of all downloading tasks are evaluated according to their importance, real-time performance, completion ratio, and queuing time. Thus, tasks with higher priorities can be activated while tasks with lower priorities are pending in the queue. This strategy helps on executing tasks with better performance first so as to properly exploit the available network bandwidth. Empirical studies show that our approach is effective in bandwidth utilization.

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