Skip to main content
On Privacy of Encrypted Speech Communications
IEEE Transactions on Dependable and Secure Computing
  • Ye Zhu, Cleveland State University
  • Yuanchao Lu, Cleveland State University
  • Anil Vikram, Cleveland State University
Document Type
Publication Date

Silence suppression, an essential feature of speech communications over the Internet, saves bandwidth by disabling voice packet transmissions when silence is detected. However, silence suppression enables an adversary to recover talk patterns from packet timing. In this paper, we investigate privacy leakage through the silence suppression feature. More specifically, we propose a new class of traffic analysis attacks to encrypted speech communications with the goal of detecting speakers of encrypted speech communications. These attacks are based on packet timing information only and the attacks can detect speakers of speech communications made with different codecs. We evaluate the proposed attacks with extensive experiments over different type of networks including commercial anonymity networks and campus networks. The experiments show that the proposed traffic analysis attacks can detect speakers of encrypted speech communications with high accuracy based on traces of 15 minutes long on average.


This work was supported in part by the US National Science Foundation (NSF) under grant No. 1144644.

Citation Information
Ye Zhu, Yuanchao Lu and A. Vikram, "On Privacy of Encrypted Speech Communications," Dependable and Secure Computing, IEEE Transactions on, vol. 9, pp. 470-481, 2012.