植基於Flash動畫之驗證碼技術

Animation CAPTCHA based on Flash

李忠澤(Chung-Tse Li)

指導教授 ： 黃國峰

國立臺中科技大學/設計學群/多媒體設計系碩士班/碩士(2009年)

摘要

驗證碼(Completely Automatic Public Turing Test to Tell Computer and Human Apart,簡稱CAPTCHA)，必須滿足幾個特色：(1)人類可以輕易的通過驗證(2)防止電腦通過驗證或提高驗證成本(3)簡單且快速的產生。本篇論文中，我們提出異於傳統使用文數字的驗證圖片，採用影像做為驗證題材，根據人類視覺在辨識物件上的優勢，以影像做為驗證題材，可以提高影像檢索的困難度；而一般影像驗證碼所面臨的最大問題為，將所有影像一次陳列會佔據較大的影像版面，以及驗證碼解答的組合數遠低於傳統文字驗證碼，因此本篇論文將利用Flash動畫之特性，設計兩個有別於一般影像驗證碼，並探討其使用性及安全性，本研究之成果除了提供種新的驗證方式之外，更可以有效增進採用Flash Player做為連結後端資料庫之介面的可行性。

關鍵字

驗證碼 ； 網路安全 ； Flash動畫

並列摘要

CAPTCHA (Completely Automatic Public Turing Test to Tell Computer and Human Apart) must satisfy the following requirements: (1) easy for human being to pass the challenge, (2) difficult to pass the challenge by computer, (3) the challenge should be generated simply and quickly. In this thesis, we propose two image-based CAPTCHA schemes, which are different from that of character-based methods. In computer vision system, it is widely known that using computer to recognize the objects in an image is more difficult than to recognize the characters in an image. Nowadays, the previous proposed Image-based CAPTCHA still have some problems: (1) display all the images at the same times will occupy too much web page layout and (2) the combinations of correct answer are too much less than that of character-based CAPTCHA. In this thesis, we use the animation characteristics of Flash to present two novel CAPTCHAs and discuss its usability and security. In additions, we have implemented the proposed methods by using MySql and PHP as remote object services.

並列關鍵字

CAPTCHA ； Web security ； Flash animation

參考文獻

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