Real-Time Encryption/Decryption of Audio Signal

Encryption is a way to secure and verify data that are traded through public communication channels in the presence of intruder party called antagonists. Consequently, the transmitted or stored message can be converted to unreadable form except for intended receivers. The decryption techniques allows intended receiver to reveal the contents of previously encrypted message via secrete keys exchanged exclusively between transmitter and receiver. The encryption and decryption techniques can be applied equally to a message in any form such as text, image, audio or video. The current paper applies and evaluate two different encryption/decryption algorithms to the real-time audio signal. The first one is the well-known RSA encryption and decryption technique, while the second one is a new suggested algorithm based on symmetric cryptography concept. The Matlab Simulink simulator tool is used for acquiring the real-time audio signal and simulating the proposed algorithms. Considering the mathematical nature of the audio signal, the experimental results showed that the RSA method yields an audio signal with low quality while the suggested algorithm yields audio signal with high quality as exact signal as the original one.