Current Proceedings on Technology

Yazarlar: Imene Bouhmadouche, Assana Diawara, Imene Bouhmadouche

Konular:-

Anahtar Kelimeler:VoIP,ITU –T G.729,Encryption,Decryption,LFSR,EMBSD,PESQ

Özet: Data security is one of the most important concerns for digital data as well as voice transmission through non-privatized networks. Thus, a significant research work is needed to provide reliable and secured data/voice transmission. The CS-ACELP algorithm based G.729 codec is standardized as voice codec by ITU-T for multimedia and Voice over Internet Protocol (VoIP) applications. In this paper we introduce a speech encryption method based Linear Feedback Shift Register (LFSR) algorithm. LFSR is suitable for speech because speech is continuous streaming data. They encrypt individual character (usually binary digits) of a plaintext message one at a time, using an encryption transformation which varies with time. We applied our encryption scheme to the standard ITU-T G.729 standard speech coder to evaluate its performance. Simulation results show that G.729 based LFSR encryption is very efficient since the encrypted speech is similar to a white noise. The perceptual evaluation of speech quality (PESQ) and enhanced modified bark spectral distortion (EMBSD) tests for speech speech extracted from TIMIT database confirm the efficiency of our proposed scheme since EMBSD of 1.636 and PESQ of 3.322 are similar to those of G.729 alone.

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