Novel Text Steganography Using Natural Language Processing and Part-of-Speech Tagging

Abstract

The practice of transmitting secret data by using cover data is called steganography. At present, several versatile steganographic methods are available using different digital objects (e.g. image, audio, video, text, etc.) as cover to hide data. Accordingly, many methods of steganalysis have been explored to reveal statistical anomalies in stego object, through which presence of secret data can be detected. However, applications of steganography and steganalysis techniques are challenging when cover object is text, as text does not have any redundant bits. In this paper, an innovative text steganography approach is proposed which uses natural language text as cover as well as secret message. The concept of shared key is also used here, that holds the count of each parts-of-speech of secret message. This key is RSA encrypted and shared with communicative parties. Stego created by this method also is in natural language text. This method is successful as the stego keeps the original meaning of the text in gross which makes it robust and undetectable. It shows good result in capacity ratio; also, the similarity index has been assessed by Jaro–Winkler distance and Generalized Levenshtein distance.

KEYWORDS:

• Data privacy
• Information security
• Natural language processing
• Public key
• Text analysis

ORCID

Barnali Gupta Banik http://orcid.org/0000-0002-8107-9501 Samir Kumar Bandyopadhyay http://orcid.org/0000-0002-4868-3459http://orcid.org/0000-0002-4868-3459

Additional information

Notes on contributors

Barnali Gupta Banik

Barnali Gupta Banik, BTech (computer science & engineering), MTech (software engineering), PhD (pursuing in computer science and engineering from University of Calcutta, Kolkata, India), currently, Assistant Professor of Computer Science & Engineering Department at St. Thomas’ College of Engineering & Technology, Kolkata. She has over 9 years of teaching experience and over 2 years of industrial experience working for MNCs in India & UK. She has authored several research papers in Network Security domain, including 7 Scopus indexed and 1 SCIE indexed articles as of date. Corresponding author. Email: [email protected].

Samir Kumar Bandyopadhyay

Samir Kumar Bandyopadhyay, BE, MTech, PhD (computer science & engineering), C. Engg., D. Engg., FIE, FIETE, Sr. Member IEEE, currently, Professor of Computer Science & Engineering, University of Calcutta, Kolkata, India. He has around 30 years of teaching, research, and administrative experience and over 300 research papers publication in International & Indian Journals and authored 5 leading text books of Computer Science & Engineering. His research interests include bio-medical engineering, mobile computing, pattern recognition, software engineering, network security etc. Email: [email protected].