Hiding the hidden message: approaches to textual steganography

Textual steganography is a means of concealing an encoded message within text. The appeal in such a system is its potential for hiding the fact that encoding is taking place. The failure to hide the presence of encoding is a form of information leakage and an inherent risk since it suggests that there is important or valuable information in transit. This is considered a major limitation of existing cryptographic techniques as applied to secure information transfer. In this paper, we describe an experimental system that we have developed as a test bed for textual steganography. This system allows us to explore the application of part of speech tagging, word sense disambiguation and synonym replacement as component strategies for textual steganography.