在無線行動的環境下, 可攜式裝置的移動所造成的問題也對點對點的技術帶來了新的挑戰. 由於可攜式裝置的移動會改變路由路徑進而影響了檔案存取的效能. 因此, 對於點對點檔案分享的技術, 在無線行動的環境下, 如何增進檔案的存取效能變成一個很關鍵的問題.

　　在本篇論文中, 為了解決上述的問題而提出了WMP2P的架構. WMP2P能根據目前網路的狀況而事先去尋找能提供較佳的檔案提供者. WMP2P主要利用 (1)the receiver-based discovery control (RDC) algorithm 去取得檔案分享者最新的狀態. (2) 當檔案傳輸中斷發生時可利用 the file provider selection (FPS) algorithm去及時選擇較佳的檔案分享者來下載所需要的檔案 (3) 並且利用 the identical file matching (IFM) algorithm來增進判斷檔案在不同的分享者是否相同的正確率. WMP2P架構的主要目的是(1)以the RDC algorithm取得檔案分享者最新的狀態來選擇較佳的分享者來下載檔案以增進檔案的存取效能 (2) 依據the FPS algorithm當傳輸中斷或發生錯誤時能快速的從其他分享者續傳而增進容錯的效率以避免不必要的延遲.

The mobility characteristic brings new challenges for research of P2P computing over the wireless
mobile networking environment. Peers’ movements in wireless mobile network change the routing path which affects the file retrieval performance. Thus, how to improve the resource discovery and retrieval for P2P file sharing applications in wireless mobile networks becomes a critical issue. In this thesis, a novel system architecture named ”WMP2P” is proposed to enable continuous resource discovery and file retrieval for mobile users in wireless mobile networks.
WMP2P (i) has a receiver-based discovery control (RDC) algorithm to obtain fresh status of peers that share files, (ii) devises a file provider selection (FPS) algorithm to select a new resource provider for mobile peers that encounter connection broken in wireless mobile networks,and (iii) adopts an identical file matching (IFM) algorithm to identify whether two files in a P2P
file sharing network are the same or not. The purpose of the WMP2P architecture is twofold: (i) improve the download performance for file retrieval by capturing fresh status of peers based on the RDC algorithm in wireless mobile network and (ii) improve fault recovery for resuming
interrupted file transfer whenever an active connection is broken due to the resource providing peer’s leave based on the FPS algorithm. The WMP2P architecture is developed to monitor the network status to make sure that a mobile user can retrieve a desired file from a resource providing peer with good connection quality. By doing this, the download performance can be improved and with the functionality of FPS and IFM algorithms in WMP2P, the fault recovery can also be improved.

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