Abstract—Text is one of the most important data that is transmitted on today’s communication networks, in the form of html WebPages, commands to access devices remotely using ssh or telnet, email etc. Confidentiality is one of the fundamental requirements for secure communication on an untrusted channel and compression is also required to conserve the bandwidth of the channel. In this study, steganography is used in a completely novel way that is different from the traditional use of steganography. Confidentiality and compression of large text using steganography is presented. In our approach text i.e. message is encoded using a grayscale bitmap image. The image acts as a steganographic carrier for the text, the carrier is never transmitted across the untrusted channel. Only the compressed index array that contains the indices for our data hidden in the image is transmitted. The image also acts as a shared key between sender and receiver, which is used for confidentiality and also to extract the desired text from the image. Encoding text into the image not only makes it secure but we achieve good amount of compression of the message that is to be sent across the channel. Results for different images and texts are compared and for every image, the length of the text is found to be directly proportional to the amount of compression.
Index Terms—Steganography, Confidentiality, Compression, Index Array, Shared image as a key
Cite: Fahad Ullah, Muhammd Naveed, Mohammad Inayatullah Babar and Faisal Iqbal, "Novel Use of Steganography for Both Confidentiality and Compression," International Journal of Engineering and Technology vol. 2, no. 4, pp. 361-366, 2010.