動態轉碼代理伺服器在網頁內容調適之應用

Abstract

隨著網際網路的蓬勃發展，全球資訊網的服務已經漸漸融入日常生活中。人們可以透過傳統的電腦，或者是其他先進的行動通訊設備（如：平版電腦、個人數位助理、手機等）來存取全球資訊網。但由於這些行動通訊設備的軟、硬體特性不同，再加上現今大部分的網頁主要都是針對傳統電腦所設計。因此，可能造成行動裝置的使用者在瀏覽網頁內容上的不便。近年來，網頁內容調適之技術已經成為一個重要的議題。如何透過各種不同的通訊設備，有效率地瀏覽網頁內容，並且滿足不同使用者的偏好便是這些技術想要達到的成果。我們可以根據調適發生的地方，將這些技術分成三大類：用戶端、代理伺服器端、伺服器端。在本論文中，我們針對伺服器端的網頁內容調適設計了一個動態轉碼代理伺服器來改進整體系統的效能。此代理伺服器主要是根據Squid所修改而來。它能夠針對適應性的網頁伺服器提供動態轉碼的功能，以及對於一般的網頁伺服器提供內容調適的功能。

As Internet grows widely, WWW has become very popular. Nowadays, people access web pages via not only desktop PC but also diverse portable devices, such as tablet PC, PDA, cell phone, etc. These devices are quite different with respect to both hardware and software capabilities. Since most web pages are mainly designed for PC users, the contents may not be suitable for these portable devices. There are many web content adaptation technologies have been proposed to deliver web content dynamically according to devices’ diverse capabilities and users’ preferences. Those adaptation technologies can be divided into three categories: client-based, proxy-based, and server-based. In this thesis, we design a dynamic transcoding proxy to enhance server-based adaptation approach. Our dynamic transcoding proxy is modified from Squid. The proposed proxy supports two kinds of functionalities which are transcoding for adaptive web server and adapting for non-adaptive web server.