Improving Confidentiality and Integrity of Syntactic Steganography by using Error Control Techniques

Abstract

Among many types of security techniques, steganography is the one that used to build private communication over the public channel. This paper proposes linguistic steganography system by utilizing lossless compression methods, error control techniques and syntax transformation of English language based embedding. The secret message is first compressed with Huffman or Shannon-Fano compression methods to achieve higher capacity. To maintain integrity and confidentiality of the secret message, Hamming code error correction and SHA-1 based Keyed-hash Message Authentication Code (HMAC) may be applied after compression according to the required security level. Because of using transformable syntax forms to carry hidden information, the imperceptibility cannot be damaged by producing meaning preserving sentences. The proposed system is evaluated by using Reuter corpus as a testing environment and Machine Translation (MT) evaluation toolkit of NIST as a similarity measuring tool. It randomly chooses 1804 sentences from about 190 files of three publication days to compare with an existing stego system. The result shows that the proposed system can enhance integrity and confidentiality of secret information by using error control techniques.