VoiceSketch: a Privacy-Preserving Voiceprint Authentication System

Voiceprint authentication is a promising approach for user authentication due to its low acquisition cost and non-contact characteristics. However, most of existing voiceprint authentication systems directly store user voiceprint templates in a database, without taking any effective measures to protect user privacy. Once the voiceprint templates in the database are leaked, user voice information becomes public, which brings severe security threats to the users and impact practical applications of a voiceprint authentication system. Few literature works study privacy-preserving voiceprint authentication although it is particularly needed. Most of existing solutions based on cryptography suffer from high computational costs. But usability of some efficient systems is poor due to additional interactions with users. To tackle the above issues, this paper proposes VoiceSketch, a privacy-preserving voiceprint authentication system based on a secure sketch to protect the privacy of user voiceprint templates with high usability. VoiceSketch does not store the voiceprint templates directly. Instead, it uses a secure sketch to correct errors between multiple voiceprint features of the same user and use cryptographic hash function to extract an authentication key from a user's voiceprint template. We analyze the security of VoiceSketch based on secure sketch and hash function. We also implement VoiceSketch and design a series of experiments to verify its accuracy and effectiveness.