臺灣博碩士論文加值系統

由於Internet之資源廣泛及個人通訊服務日漸重要；就使用者之觀點而言，希望能以各種不同的通訊設備，能夠很容易且有效率地來擷取WWW資源。就網頁內容提供者之觀點而言，所面臨之問題即是：如何在具有不同性能(Capability)的通訊設備及不同的網路資源下，來滿足不同使用者所偏好（Preference）的設定。CC/PP是W3C近年來所提出的標準，用以形容通訊時的性能與環境。透過CC/PP的交換協定，WWW使用者得以將通訊的配備、環境及個人偏好設定，傳送給網頁內容提供者，以達成性能協商的目的。在本論文中，我們提出一個能夠有效利用網路頻寬及使用者配備性能與偏好設定的Internet存取架構，以提供WWW資訊服務一個解決方案。

As Internet becomes the most important information source, people desire to access Internet contents anywhere, anytime with any device. However, the expansion of the Internet also comes with increasing diversity and heterogeneity in terms of client devices capability, network bandwidth and user preferences. Internet content providers must offer the most adequate services relevant with individual characteristics. CC/PP (Composite Capabilities and Preference Profiles), proposed by W3C recently, is a standard of describing user agent’s capabilities and preferences. WWW clients convey capabilities and preferences by means of CC/PP exchange protocol to servers, and then capabilities negotiation is made. In this thesis, a web content adaptation system, which can detect bandwidth dynamically and adapt various capabilities and preferences of clients, is proposed. This system is developed to produce an adequate response for the request. Thus, content personalization and universal access is realized and network payloads are alleviated indirectly.

Contents
Abstract (in Chinese) i
Abstract (in English)ii
Acknowledgementsiii
Contentsiv
List of Figuresvi
List of Tables viii
1.Introduction………………………………………………………….1
2. Background Knowledge………………………………………………7
2.1 Joint Photographic Experts Group (JPEG)……………………7
2.2 Content negotiation………………………………………………9
2.2.1 WAP User Agent Profile……………………………………….9
2.2.2 Composite Capabilities and Preferences Profiles (CC/PP)…………………………………………………………………………….17
2.3 Measuring Network Bandwidth……………………………………22
2.3.1 Packet Pair Algorithm…………………………………………22
2.3.2 Pathchar Algorithm…………………………………………….24
2.4 Extension Markup Language (XML)………………………………26
3. System Architecture……………………………………………….31
3.1 Overview of the System Architecture..………………………31
3.2 Content Analysis.…………………………………………………33
3.3 CC/PP Filter…….…………………………………………………36
3.4 Bandwidth Probe Engine…………………………………….……43
3.5 Decision Maker………………………………………………….…43
3.6 Rendering Module………………………………………………….45
4. Implementation………………………………………………………46
4.1 Development Environment…………………………………………46
4.2 Implementation Result……………………………………………49
5. Conclusion……………………………………………………………56
Reference…………………………………………………………………57

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