Notestega: Notes-based Steganography Methodology
Abdelrahman Desoky · Information Security Journal A Global Perspective · 2009
The wide use of Notes in business, science, education, news, etc., renders Notes attractive steganographic carriers and allows the communicating parties to establish a covert channel that is capable of transmitting messages in an unsuspicious way. The presented Notes-based Steganography Methodology (Notestega) takes advantage of the recent advances in automatic notetaking techniques to generate a text cover. Notestega neither exploits noise (errors) to embed a message nor produces a detectable noise. Instead, it pursues the variations among both human notes and the outputs of automatic notetaking techniques to conceal data. Virtually, it is accomplished in three steps. First, Notestega generates a number of legitimate various notes of the same input. Second, based on a predetermined protocol it picks a particular note, for example, note number 1, 2, or 5. Third, Notestega substitutes some of the text in the selected note with another text taken from the unpicked notes. Such text substitution is carefully done to avoid the introduction of a suspicious pattern while embedding a message. Unlike machine translation and automatic summarizer, automatic notetaking can embed nondirectly related elements to its output including linguistic elements, for example, sentences, words, or abbreviations, and nonlinguistic elements, for example, lines, stars, arrows, or symbols, and thus the generated note-cover (text-cover) has ample room of concealing data. The presented implementation and steganalysis validation of Notestega demonstrate distinct capabilities of achieving the steganographic goal, adequate room for concealing data, and a superior bitrate to contemporary text steganography approaches, which is roughly 7.777%.