Page 89 - 2024-Vol20-Issue2

Received: 4 December 2023 | Revised: 2 February 2024 | Accepted: 3 February 2024

DOI: 10.37917/ijeee.20.2.8 Vol. 20 | Issue 2 | December 2024

Open Access

Iraqi Journal for Electrical and Electronic Engineering

Review Article

Study of Chaotic-based Audio Encryption Algorithms: A

Review

Alaa Shumran* and Abdul-Basset A. Al-Hussein
Electrical Engineering Department, College of Engineering University of Basrah, Basrah, Iraq

Correspondance
*Alaa Shumran
Electrical Engineering Department, University of Basrah, Basrah, Iraq
Email: pgs.alaash@uobasrah.edu.iq

Abstract
Nowadays, multimedia communication has become very widespread and this requires it to be protected from attackers
and transmitted securely for reliability. Encryption and decryption techniques are useful in providing effective security
for speech signals to ensure that these signals are transmitted with secure data and prevent third parties or the public
from reading private messages. Due to the rapid improvement in digital communications over the recent period up to the
present, the security of voice data transmitted over various networks has been classified as a favored field of study in
earlier years. The contributions to audio encryption are discussed in this review. This Comprehensive review mainly
focuses on presenting several kinds of methods for audio encryption and decryption the analysis of these methods with
their advantages and disadvantages have been investigated thoroughly. It will be classified into encryption based on
traditional methods and encryption based on advanced chaotic systems. They are divided into two types, continuous-time
system, and discrete-time system, and also classified based on the synchronization method and the implementation
method. In the fields of information and communications security, system designers face many challenges in both
cost, performance, and architecture design, Field Programmable gate arrays (FPGAs) provide an excellent balance
between computational power and processing flexibility. In addition, encryption methods will be classified based on
Chaos-based Pseudo Random Bit Generator, Fractional-order systems, and hybrid chaotic generator systems, which is
an advantageous point for this review compared with previous ones. Audio algorithms are presented, discussed, and
compared, highlighting important advantages and disadvantages. Audio signals have a large volume and a strong
correlation between data samples. Therefore, if traditional cryptography systems are used to encrypt such huge data,
they gain significant overhead. Standard symmetric encryption systems also have a small key-space, which makes them
vulnerable to attacks. On the other hand, encryption by asymmetric algorithms is not ideal due to low processing speed
and complexity. Therefore, great importance has been given to using chaotic theory to encode audio files. Therefore,
when proposing an appropriate encryption method to ensure a high degree of security, the key space, which is the critical
part of every encryption system, and the key sensitivity must be taken into account. The key sensitivity is related to the
initial values and control variables of the chaotic system chosen as the audio encryption algorithm. In addition, the
proposed algorithm should eliminate the problems of periodic windows, such as limited chaotic range and non-uniform
distribution, and the quality of the recovered audio signal remains good, which confirms the convenience, reliability, and
high security.

Keywords
Audio encryption, chaotic systems, FPGA, Synchronization, and Fractional-order Systems.

I. INTRODUCTION

Securing speech communication is critical to many businesses,
including corporate, military, voice-over IP, and private voice

This is an open-access article under the terms of the Creative Commons Attribution License,
which permits use, distribution, and reproduction in any medium, provided the original work is properly cited.
©2024 The Authors.
Published by Iraqi Journal for Electrical and Electronic Engineering | College of Engineering, University of Basrah.

https://doi.org/10.37917/ijeee.20.2.8 |https://www.ijeee.edu.iq 85