臺灣博碩士論文加值系統

由於網際網路（Internet）的快速成長，使得網路頻寬需求以指數型的成長，造成網路壅塞。Proxy-caching和Mirroring藉由資源再利用，降低重複網路存取，提供了一個可能的解決方案。
在本文中，我們分析FTP Mirroring與Caching的作法，並比較其異同，希望提出一個結合Mirroring與Caching的架構，並且藉由使用者檔案上傳和檔案預約的機制，完成一套由需求驅動的網路資源共享系統。
我們可以將代理伺服器快取的檔案，自動分類複製後存到檔案伺服器提供下載，讓原本無法被使用者直接存取的快取檔案，可再利用，進而減少頻寬浪費。此方法不同於傳統檔案伺服器由管理者驅動複製檔案的模式，而是改由使用者來驅動複製。同時可以利用檔案上傳和檔案預約的方式，反應使用者需求，減少複製不符需求檔案的機率，並讓使用者在複製過程中提供資訊，協助檔案自動分類及產生說明檔。
根據實作的結果，系統複製快取檔案到檔案傳輸伺服器，確實讓系統檔案再利用率隨之提昇，而且搭配FTP Archie Server或搜尋引擎一併使用，可讓再利用率大幅提昇，顯示本系統確實網路資源共享及降低流量上有不錯的成效。

The Internet traffic continues to increase explosively, and meanwhile the demand on network bandwidth grows at exponential rate. Current techniques that could reduce latency, network bandwidth demand, and server load include proxy-caching and mirroring. These approaches solve such network traffic problems by reusing existing Internet objects.
In the thesis, we propose a Mirror-On-Demand Server to achieve a demand-oriented Internet object sharing system. MOD Server has following features:
- integration with mirroring and proxy-caching
- file-uploading and file-ordering services
- little extra bandwidth use
- low administration overhead
MOD System can automatically replicate and classify cached Internet objects into the FTP mirror server. It also decreases the overhead of administration. Invisible cached objects can be downloaded directly by users, with the result that the reutilization of cached object increases. Furthermore, we adopt the file-uploading and file-ordering mechanisms to reflect the responses of user demands. Besides replicating popular Internet objects, we can also automatically classify and produce a description file of the object according to the information that users fill in during the operations of file-uploading and file-ordering.
Based on results of our experiments, it shows that our system can increase the reutilization of cached Internet objects. It reveals that our system achieves the sharing of Internet objects and reduces the latency and the wastage of network bandwidth indirectly.

第一章 緒論
1.1研究背景
1.2研究目標
1.3論文架構
第二章 相關研究
2.1 使用者存取網路檔案之行為分析
2.2 分散式檔案系統
2.2.1 NFS檔案系統和AFS檔案系統
2.2.2 Alex檔案系統
2.2.3 WebNFS、WebFS、CIFS
2.2.4 Mirror Server
2.2.5 Proxy Cache Server
2.2.6 Mirroring vs. Caching
2.3 HENSA Caching FTP Server
2.4 網際網路之相關研究探討
2.4.1 檔案預取（Prefetching）
2.4.2 檔案的分類索引
第三章 問題探討
3.1 複製檔案的方法
3.2 複製檔案的過濾
3.3 熱門檔案的判斷
3.4 命名（Naming）
3.5 增加檔案再利用率
第四章 系統設計與考量
4.1 系統設計考量
4.1.1 與既有的代理伺服器搭配運作
4.1.2 Web相關研究的適用性
4.1.3 收集分析使用者存取行為模式
4.1.4 檔案自動過濾複製與分類
4.1.5 檔案上傳與預約推薦下載
4.2 系統特色
4.3 系統架構
第五章 系統實作與效能評估
5.1 系統實作
5.1.1 系統配備及實作環境
5.1.2 系統實作狀況
5.2 系統效能評估
第六章 結論
參考文獻

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