適用於P2P檔案分享系統傳輸協定之設計

Abstract

近年來分散式P2P檔案共享系統因可擴張性較佳而廣為風行。但是，在非對稱網路之下，受到兩個問題之影響，其效能受到很大的限制：(1) Fractional Upward Bandwidth (FUB)與 (2)Blockage of Acknowledgement (BoA)。本研究之目的，是要改良網路協定中的傳輸層 (Transport Layer) 協定以提昇P2P檔案分享系統之效能。我們改用UDP作為傳輸層協定，並在應用層加入封包等級錯誤更正(Packet Level Error Correction)及決定資料傳送速率(Date Rate Determination)等機制，以彌補UDP之缺陷。文中並提供傳輸協定運作時所需參數的估計法，並且與其它傳輸協定做效能之比較。實驗結果發現，我們設計的傳輸協定確可改善P2P檔案共享系統的運作效能。

Distributed Peer-to-Peer (P2P) sharing system are widely used due to its scalability. Unfortunately, P2P file sharing system has several shortcomings on performance over asymmetric networks, due to two main problems: Fractional Upward Bandwidth and Blockage of Acknowledgement. We propose a new UDP-based protocol to alleviate the problems. Experiments show that our proposed protocol can improve its performance.