A Study of Webpage Data Hiding Scheme based on Modular Operation

[[abstract]]資訊快速發展的時代下，Internet為人們生活帶來許多便利，只要連上網路就可以快速得到想要的資訊，如：傳遞訊息、資料查詢、影像傳送...等。然而在網路發達的環境下傳遞個人訊息也更容易產生資訊安全疑慮。使用加密演算法(例:DES, AES, RSA... 等) 將資料先行加密後再傳遞可達到安全傳送資料的目的，但是資料經過加密後就像亂碼一樣反而容易引起有心人士的關注，進而影響到資訊傳送的安全性。資訊隱藏技術提供了另外一個安全的資料傳遞方式讓安全性提升。主要是先將資料加密後再藉由負載媒體攜帶機密資訊後傳送到接收端，由於負載媒體通常是一般的多媒體檔案、文字檔或網頁資料，因此可避免有心人士對傳送資料過於關注。我們觀察在靜態網頁藏入機密資訊時使用LSB是一種簡單而常見的作法，但是其直接修改CSS裡的各種設定的參數值的作法所造成的誤差(或稱失真)可以進一步降低。本研究主要在探討如何在靜態網頁的CSS設計參數裡使用LSB及模運算的策略降低參數修改後所產生的誤差，如此一來，藏有機密資訊的網頁將更不容易被人發現有異樣，進一步提高成功達到使用靜態網頁傳遞機密資訊的目的。接收者只需要去解析靜態網頁上的HTML標籤即可取出加密後的機密資訊，接收者再用解密金鑰對取出的資料解密後便可查看訊息內容。 Because of the rapid development of networking and information technique, sharing the multimedia data to the receiver over the networking become one of most import in the user’s daily life. As we know, the Networks is unsafe for sending personal data over the network. Security is one of the most important factor for sending secret data over computer networks. Maybe you can encrypt the secret data as a meaningless datagram. However, a random message is more attractive for the unexpected user to pay attention on it. Thus, using Steganography (also know Information Hiding or Data Hiding) to conceal the secret data can significant improve the security for secret data delivery over the computer networks. The LSB substitution is a straight forward strategy to conceal secret data into the coefficients in a webpage. Again, the distortion generated by the LSB strategy will make the webpage data deliver has some risk because the stego webpage is look not truly the same with the original webpage. In this study, we are focus on reducing the distortion after data has been concealed in the webpage. Thus, the Modular operations is adapted in the proposed method