Audio steganography with AES for real-time covert voice over internet protocol communications

• Published in: Science China. Information sciences Vol. 57; no. 3; pp. 71 - 84
• Main Authors: Tang, ShanYu, Jiang, YiJing, Zhang, LiPing, Zhou, ZhangBing
• Format: Journal Article
• Language: English
• Published: Heidelberg Science China Press 01.02.2014; Springer Nature B.V
• Subjects: AES-128; Algorithms; Audio signals; Codec; Communication; Communications systems; Computer Science; Cryptography; Cybersecurity; Embedding; Encryption; Information Systems and Communication Service; Internet Protocol; Internet telephony; IP (Internet Protocol); IP通信; Mann-Whitney U test; Messages; Performance evaluation; Real time; Research Paper; State-of-the-art reviews; Statistical analysis; Steganography; Telephones; Time synchronization; Voice; Voice communication; VoIP (protocol); 互联网协议; 实时服务; 语音; 隐写术; 隐蔽; 音频信号; VoIP; covert communication; steganography; Mann-Whitney-Wilcoxon; AES
• ISSN: 1674-733X; 1869-1919
• DOI: 10.1007/s11432-014-5063-2

As a popular real-time service on the Internet, Voice over Internet Protocol （VoIP） communication attracts more and more attention from the researchers in the information security field. In this study, we proposed a VoIP steganographic algorithm with variable embedding capacities, incorporating AES and key distribution, to realize a real-time covert VoIP communication. The covert communication system was implemented by embedding a secret message encrypted with symmetric cryptography AES-128 into audio signals encoded by PCM codec. At the beginning of each VoIP call, a symmetric session key （SK） was assigned to the receiver with a session initiation protocol-based authentication method. The secret message was encrypted and then embedded into audio packets with different embedding algorithms before sending them, so as to meet the real- time requirements of VolP communications. For each audio packet, the embedding capacity was calculated according to the specific embedding algorithm used. The encryption and embedding processes were almost synchronized. The time cost of encryption was so short that it could be ignored. As a result of AES-based steganography, observers could not detect the hidden message using simple statistical analysis. At the receiving end, the corresponding algorithm along with the SK was employed to retrieve the original secret message from the audio signals. Performance evaluation with state-of-the-art network equipment and security tests conducted using the Mann-Whitney-Wilcoxon method indicated that the proposed steganographic algorithm is secure, effective, and robust.