Abstract
New hybrid cryptosystems represent a highly effective method for increasing security levels of Voice over Internet Protocol (VoIP) systems. In this paper, a dual-security cryptosystem for VoIP voicemail is proposed based on two-factor authentication, followed by Baker Map and RC6 encryption. Two security system models are proposed: the first involves biometric voiceprint encryption with pin code, and the second involves dual-biometric encryption via voiceprint with fingerprint. Parameters were selected to assess the proposed security systems for both quality of function and real-life practicality. An experiment was conducted with a true VoIP call manager, VoIP terminals and fingerprint reader. In addition, Visual Basic and MATLAB were utilized for development and testing of the new cryptosystems. Behind this orthogonal frequency division multiplexing (OFDM) simulation system was developed to ensure efficiency with different signal-to-noise ratio (SNR). Comparative analysis among both encryption methods determined that the first scenario is more cost-effective than the second owing to the lack of fingerprint-reading device, but the second is more secure due to combined biometric print requirements. A comparison with techniques used by other, recently developed voice cryptosystems demonstrated lower correlation coefficient (25% improvement) and encryption processing time by the presented hybrid cryptosystem. Collectively, this paper presents a VoIP system with high security and immunity vis-a-vis image encryption noise.