The trade-off between security and quality using permutation and substitution techniques in speech scrambling system

Abstract

Speech is one of the means of communication between people throughout the universe, so people want to communicate with each other no matter how far away since wireless networking offers, this feature, the freedom to connect from anywhere and anytime. Because speech is used extensively in wireless networks, it takes much time to encrypt it using well-known cryptographic algorithms, so, speech scrambler techniques have been used in the modern communication systems to overcome this problem. It has proven its presence in protecting data transmitted over wireless networks in the past few years. The main objective of this paper is to compare the systems that use process permutation with the systems that use the substitution process in the speech scrambling technique to protect speech information. To find out which is better use the permutation process or substitution in the technique of speech scrambling in terms of security and quality, security and quality results we will compare between our proposed system, which uses permutation process, with another system, uses substitution process. Based on the values of the segmental signal-to-noise ratio measure (SSNR), Comparison of the above two systems will take place because it used in both systems to evaluate the performance of the system in terms of security and quality of the recovered speech.