SkyDe: a Skype-based Steganographic Method

  • Wojciech Mazurczyk Warsaw University of Technology
  • Maciej Karaś Warsaw University of Technology
  • Krzysztof Szczypiorski Warsaw University of Technology

Abstract

This paper introduces SkyDe (Skype Hide), a new steganographic method that utilizes Skype encrypted packets with silence to provide the means for clandestinecommunication. It is possible to reuse packets that do not carry voice signals for steganographic purposes because Skype does not use any silence suppression mechanism.The method’s proof-of-concept implementation and first experimental results are presented. They prove that the method is feasible and offers steganographic bandwidth as high as 2.8 kbps.

References

[1] Mazurczyk, W. (2013); VoIP Steganography and Its Detection - A Survey, ACM Computing Surveys (accepted for publication), ISSN 0360-0300.

[2] Mazurczyk, W.; Szczypiorski, K. (2008); Steganography of VoIP Streams, In Proc. of 3rd Int Symp Information Security (IS'08), Monterrey, Mexico, 1001-1018.

[3] Huang, Y.; Tang, S.; Yuan, J. (2011); Steganography in Inactive Frames of VoIP Streams Encoded by Source Codec, IEEE Transactions on information forensics and security, ISSN 1556-6013, 6(2):296-306.

[4] Wang, X., Chen, S., Jajodia, S. (2005); Tracking anonymous peer-to-peer VoIP calls on the internet, In Proc. of 12th ACM CCS '05, 81-91.

[5] Caukin, J. (2012); 35 Million People Concurrently Online on Skype, Skype Big Blog, URL: http://blogs.skype.com/en/2012/03/35_million_people_concurrently.html.

[6] Lubacz, J.; Mazurczyk, W.; Szczypiorski, K. (2010); Vice over IP, IEEE Spectrum, ISSN 0018-9235, 40-45

[7] Timberg, C.; Nakashima, E. (2012); Skype makes chats and user data more available to police, URL: http://www.washingtonpost.com/business/economy/ skype-makes-chats-and-user-data-more-available-to-police/2012/07/25/ gJQAobI39W_story.html

[8] Bonfiglio, D.; Mellia, M.; Meo, M.; Rossi, D.; Tofanelli, P. (2007);Revealing Skype traffic: when randomness plays with you, In Proc. of SIGCOMM '07, NY, USA, 37-48.

[9] Bonfiglio, D.; Mellia, M.; Meo, M.; Ritacca, N.; Rossi, D. (2008); Tracking Down Skype Traffic, In Proc. of IEEE INFOCOM '08, Phoenix, USA.

[10] Chang, Y.C.; Chen, K.T.; Wu, C.C.; Lei, C.-L. (2008); Inferring speech activity from encrypted Skype traffic, In Proc. of IEEE Globecom '08, Los Alamitos, USA, 1-5.

[11] Molnar, S.; Perenyi, M. (2011); On the identification and analysis of Skype traffic, International Journal of Communication Systems, ISSN 1074-5351, 24(1):94-117.

[12] Iwano, Y., Sugita, Y., Kasahara, Y., Nakazato, S., Shirai, K. (1997); Difference in visual information between face to face and telephone dialogues, In Proc. of IEEE ICASSP '97, 1499-1502.

[13] Berger, J.; Hellenbart, A.; Weiss, B.; Moller, S.; Gustafsson, J.; Heikkila, G. (2008); Estimation of quality per call in modelled telephone conversations, In Proc. of IEEE ICASSP'08, 4809-4812.

[14] Garofolo, J.S. et al. (1993); TIMIT Acoustic-Phonetic Continuous Speech Corpus Linguistic Data Consortium, Philadelphia, USA.

[15] ITU-T (2001); Recommendation. P.862. Perceptual evaluation of speech quality (PESQ): An objective method for end-to-end speech quality assessment of narrow-band telephone networks and speech codecs.

[16] ITU-T (1996); Recommendation. P.800. Methods for subjective determination of transmission quality.

[17] Hamdaqa, M.; Tahvildari, L. (2011); ReLACK: A Reliable VoIP Steganography Approach, In Proc. of 5th International Conference on Secure Software Integration and Reliability Improvement (SSIRI '11), Korea, 189-197.

ReLACK: A Reliable VoIP Steganography Approach, In Proc. of 5th International Conference on Secure Software Integration and Reliability Improvement (SSIRI '11), Korea, 189-197.

[18] TeleGeography Report (2012); International Call Traffic Growth Slows as Skype's Volumes Soar, URL: http://www.telegeography.com/press/press-releases/2012/01/09/ international-call-traffic-growth-slows-as-skypes-volumes-soar/index.html

[19] IEEE (2004); I. S. 802.16-2004, IEEE standard for local and metropolitan area networks part 16: Air interface for fixed broadband wireless access systems.

[20] Wright, C.; Ballard, L.; Coulls, S.; Monrose, F.; Masson, G. (2008); Spot me if you can: recovering spoken phrases in encrypted VoIP conversations. In Proc. of IEEE Symposium on Security and Privacy, May, 2008
Published
2013-06-02
How to Cite
MAZURCZYK, Wojciech; KARAŚ, Maciej; SZCZYPIORSKI, Krzysztof. SkyDe: a Skype-based Steganographic Method. INTERNATIONAL JOURNAL OF COMPUTERS COMMUNICATIONS & CONTROL, [S.l.], v. 8, n. 3, p. 432-443, june 2013. ISSN 1841-9844. Available at: <http://univagora.ro/jour/index.php/ijccc/article/view/469>. Date accessed: 19 jan. 2021. doi: https://doi.org/10.15837/ijccc.2013.3.469.

Keywords

Information hiding, network steganography, Skype