Informatics Publishing Limited

Tamer M. Barakat ¹

Affiliations
1 Electrical Engineering Department, Fayoum University, Fayoum, EG

Abstract

We propose a new public key cryptosystem which named PQK that based on the decisional Diffie-Hellman problem. The scheme is provably secure against adaptive chosen cipher-text attack under the hardness assumption of the decisional Diffie-Hellman problem. Compared with the RSA public key scheme, our scheme has nice features: (1) our scheme is provably secure against adaptive chosen cipher-text attack under the intractability paradigm, (2) the PQK is secure against other attacks such as common modulus attack and low exponent attack which the RSA is still suffered from these attacks, and (3) it is faster than, in the decryption process, the RSA cryptosystem.

Keywords

RSA Cryptosystem, PQK Cryptosystem, Adaptive Chosen Ciphertext Attack, Low Exponent Attack, Common Modulus Attack.

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Amr M. Gody ¹, Safey A. Abdelwahab ², Tamer M. Barakat ¹, Mohamed Y. Mohamed ²

Affiliations
1 Electrical Engineering Department, Fayoum University, EG
2 Engineering Department, Nuclear Research Center, Atomic Energy Authority, EG

Abstract

Speech compression is one area of digital signal processing that focusing on reducing the bit rate of the speech signal for transmission or storage without significant loss of quality. This paper presents a new design feature for speech Compression using Wavelet Packet Transform and Linear prediction Coding. The proposed algorithm uses best tree decomposition of wavelet packets, which develop features afterward compressed signal is compressed by Linear prediction Coding. The 4 points encoded vector is a full of information just like the original best tree’s structure. The implied scoring system makes BTE suitable for compression problems and we reach at 12 compression ratio. The performance of speech signal is measure on the basis of signal to noise ratio (SNR), mean square error (MSE) and peak signal to noise ratio (PSNR).

Keywords

Speech Compression, Wavelet Packet Transform, BTE, LPC.

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