Encryption Process Research Articles

A new mathematical model to improve encryption process based on Split-Radix Fast Fourier Transform algorithm

This paper introduces a new encryption method aimed at improving the cryptography process through the use of splitting radix Fourier Transform technique called Split-Radix Fast Fourier Transforms (SRFFT). The proposed method is based on splitting the FFT radix-2 and radix-4 algorithms to achieve improved information assurance by SRFFT two phases. The first phase applies direct computation of SRFFT algorithm on input plaintext to produce a ciphertext and the second phase applies the reversing SRFFT algorithm to decipher. Several types of cryptoanalysis attacks such as brute-forcing, autocorrelation and dictionary attacks are comparatively evaluated and the end result of SRFFT evaluation indicates that SRFFT is preferable in many practical encryption applications since SRFFT complexity increases with the range of split-radix computations thus eliminating the potential chances of cryptanalysis attacks.

On the Search for Supersingular Elliptic Curves and Their Applications

Elliptic curves with the special quality known as supersingularity have gained much popularity in the rapidly developing field of cryptography. The conventional method of employing random search is quite ineffective in finding these curves. This paper analyzes the search of supersingular elliptic curves in the space of curves over Fp2. We show that naive random search is unsuitable to easily find any supersingular elliptic curves when the space size is greater than 1013. We improve the random search using a necessary condition for supersingularity. As our main result, we define for the first time an objective function to measure the supersingularity in ordinary curves, and we apply local search and a genetic algorithm using that function. The study not only finds these supersingular elliptic curves but also investigates possible uses for them. These curves were used to create cycles inside the isogeny graph in one particular application. The research shows how the design of S-boxes may strategically use these supersingular elliptic curves. The key components of replacement, which is a fundamental step in the encryption process that shuffles and encrypts the data inside images, are S-boxes. This work represents a major advancement in effectively identifying these useful elliptic curves, eventually leading to their wider application and influence in the rapidly expanding field of cryptography.

Data Shuffling and Data Blocks Shuffling Method for Digital Data Signals Protection

In this paper, a new method for digital data cryptography is proposed to increase the speed of data cryptography, simplify the processes of data encryption - decryption, and to strengthen the degree of data protection. The proposed data shuffling and data blocks shuffling (DS_DBS) method is able to process messages, gray images, color images and digital speech file using the same encryption and decryption functions; changing the digital data type will not require any changes in the aforesaid functions. The proposed DS_DBS method allows data blocking (block size will be variable), and it is determined by the private key. Data encryption is applied by simple data shuffling and data blocks shuffling, while data decryption is applied by shuffling back the data blocks and shuffling back the data. These shuffling operations replace the complex logical and arithmetic operations used in other existing methods of data cryptography. The shuffling and shuffling back operations are implemented based on two secret indices keys, obtained by running two chaotic logistic map models. The proposed method utilizes a long private key with a variable length that depends on the selected number of crypto phases. It can be implemented in one or more phases; each phase is a function call to execute the encryption-decryption functions with the associated inputs. Using more than a phase, increases the security level by using longer private key, and each phase will be independent. The encrypted-decrypted result of each phase can be taken as a final result. Implementing the proposed DS_DBS method - using various data types – and examining its speed reveal not only the enhanced speed of data cryptography, but also the better quality and sensitivity of the proposed method compared to those of existing state of the art cryptography methods.

Multispectral Integrated Black Arsenene Phototransistors for High-Resolution Imaging and Enhanced Secure Communication.

The demand for broadband, room-temperature infrared, and terahertz (THz) detectors is rapidly increasing owing to crucial applications in telecommunications, security screening, nondestructive testing, and medical diagnostics. Current photodetectors face significant challenges, including high intrinsic dark currents and the necessity for cryogenic cooling, which limit their effectiveness in detecting low-energy photons. Here, we introduce a high-performance ultrabroadband photodetector operating at room temperature based on two-dimensional black arsenene (b-As) nanosheets. This device demonstrates responsivity across visible, near-infrared, and THz spectral ranges, with responsivities reaching 91.6 A/W at 520 nm, 6.3 A/W at 1550 nm, and 7.8 V/W at 0.27 THz. The exceptional THz responsivity is attributed to the use of plasma-wave rectification in antenna-integrated field-effect transistors with asymmetric antennas, enhancing light-matter interaction and facilitating nonlinear rectification within the two-dimensional electron gas of the transistor channel, achieving a voltage-dependent bipolar response. These advanced b-As-based photodetectors also enable secure THz communication through complex logic operations, achieving robust data encryption and high-performance signal processing.

Design of Malicious Hardware Trojans in AES Crypto system

Hardware Trojans pose a significant threat to the security and integrity of cryptographic systems, particularly in Advanced Encryption Standard (AES) implementations, which are widely used in securing sensitive data. These malicious modifications to integrated circuits (ICs) can compromise the confidentiality and reliability of AES cryptographic operations by introducing covert backdoors, information leakage channels, or functional disruptions. Hardware Trojans are typically designed to evade detection during design-time validation and post-manufacturing testing, often activating only under specific triggers such as rare input patterns or environmental conditions. In AES systems, Trojans can manipulate the encryption process by leaking secret keys through side-channel information such as power consumption, timing variations, or electromagnetic emissions. Some Trojans directly alter the encryption algorithm, weakening the cryptographic strength and rendering encrypted data vulnerable to attacks. Attackers may also embed Trojans at the Register Transfer Level (RTL) or gate-level design, leveraging the inherent complexity of AES circuits to conceal their presence. Detection and mitigation of hardware Trojans in AES implementations are challenging due to their stealthy nature. Techniques such as side-channel analysis, functional verification, and static code analysis have been developed, but sophisticated Trojans often bypass these methods. Advanced countermeasures include runtime monitoring, hardware obfuscation, and Trojan-resilient design methodologies. This paper explores the implications of hardware Trojans in AES cryptographic systems, analysing their design, potential attack vectors, and impacts on data security. Furthermore, it discusses state-of-the-art detection and prevention techniques, highlighting gaps and future research directions. Given the critical role of AES in securing financial, military, and consumer data, addressing the hardware Trojan threat is paramount to ensuring trust in cryptographic hardware and safeguarding against adversarial exploitation.

Transmission of High Data Rate Signals over Low-Frequency Passbands Using (DSSS-BPSK) Technique

This study presents an enhancement to the Direct Sequence Spread Spectrum (DSSS) algorithm aimed at transmitting high data rate signals over low-frequency passbands. By utilizing a random number to generate a new encryption key, the complexity of both encryption and decryption processes is significantly increased. The original signal undergoes multiplication with a spreading code, resulting in a random matrix that obscures the original data and enhances security. The research employs Binary Phase Shift Keying (BPSK) modulation to effectively transmit the spread signal, optimizing bandwidth utilization and mitigating channel impairments. Simulation results conducted using MATLAB demonstrate that the proposed DSSS method achieves low Bit Error Rates (BER) under various conditions, confirming its robustness against interference. Furthermore, the findings indicate that the combination of high data rate transmission and low-frequency passbands using DSSS has promising applications in diverse fields such as industrial automation, remote sensing, and military communications. Overall, this research contributes to advancing secure and efficient communication systems by leveraging DSSS techniques.

Unveiling Sybil Attacks Using AI‐Driven Techniques in Software‐Defined Vehicular Networks

ABSTRACTThe centralized nature of software‐defined networks (SDN) makes them a suitable choice for vehicular networks. This enables numerous vehicles to communicate within an SD‐vehicular network (SDVN) through vehicle‐to‐vehicle (V2V) and with road‐side units (RSUs) via vehicle‐to‐infrastructure (V2I) connections. The increased traffic volume necessitates robust security solutions, particularly for Sybil attacks. Here, the attacker aims to undermine network trust by gaining unauthorized access or manipulating network communication. While traditional cryptography‐based security methods are effective, their encryption and decryption processes may cause excess delays in vehicular scenarios. Previous studies have suggested machine learning (ML) like AI‐driven approaches for Sybil attack detection in vehicular networks. However, the primary drawbacks are high detection time and feature engineering of network data. To overcome these issues, we propose a two‐phase detection framework, in which the first phase utilizes cosine similarity and weighting factors to identify attack misbehavior in vehicles. These metrics contribute to the calculation of effective node trust (ENT), which helps in further attack detection. In the second phase, deep learning (DL) models such as CNN and LSTM are employed for further granular classification of misbehaving vehicles into normal, fault, or Sybil attack vehicles. Due to the time series nature of vehicle data, CNN and LSTM are used. The methodology deployed at the controller provides a comprehensive analysis, offering a single‐ to multi‐stage classification scheme. The classifier identifies six distinct vehicle types associated with such attacks. The proposed schemes demonstrate superior accuracy with an average of 94.49% to 99.94%, surpassing the performance of existing methods.

ANALISA DAN PERANCANGAN SISTEM INFORMASI ENKRIPSI DATA DENGAN ALGORITMA VIGENERE CHIPER BERBASIS WEB

Cryptography is a field of knowledge that uses mathematical equations to perform encryption and decryption processes. This technique is used to convert data into certain codes, with the aim that the stored information cannot be read by anyone except those who have the right. In this study, a cryptography learning application was designed that implements encryption and decryption methods using the Vigenere cipher method. The results of the study are a cryptography learning application using the Vigenere cipher method that can encode secret messages and also help increase the understanding of users who want to learn about cryptography, especially the Vigenere cipher method.

Vulnerability Detection and Improvements of an Image Cryptosystem for Real-Time Visual Protection

Chaos-based cryptosystems are regarded as highly secure techniques for image encryption. However, despite the considerable enhancement of encryption robustness provided by chaotic systems, security vulnerabilities may still arise, potentially leading to drastic damage in contexts involving sensitive data such as medical or military images. Identifying these vulnerabilities and developing corresponding countermeasures are essential to prevent security breaches and achieve higher protection. From this perspective, this research thoroughly examines the security of an image encryption scheme based on the 1D sine-powered chaotic map. This analysis identifies vulnerabilities within the scheme that can reduce it to a permutation-only scheme. Exploiting the found vulnerabilities, three distinct cryptanalysis attacks are proposed in this work. These attacks enable unauthorized individuals to replicate the encryption and decryption processes without possessing the secret key, posing significant security risks. Under ciphertext-only attack, chosen-plaintext attack, and chosen-ciphertext attack conditions, the proposed attacks demonstrate their effectiveness through simulation and experimentation. Notably, the results indicate that these attacks can be executed within seconds and using only a few special plaintext or ciphertext images. An improved version of the analyzed scheme is introduced to address the identified vulnerabilities and enhance its security and speed.

A LE-controlled 4D non-degenerate hyperchaotic system and STP-CS model based efficient image encryption algorithm

Abstract Restricted by the environment and hardware equipment resources, existing chaotic systems have shortcomings such as low complexity, low randomness, and chaotic degradation phenomena, which in turn cause the security risks of chaotic image encryption algorithms. To overcome these issues, this paper proposes a method for the construction of a LE-controlled four-dimensional (4D) non-degenerate discrete chaotic system. Numerical analysis has demonstrated that the developed system possess high complexity and unpredictability. Based on the developed chaotic system, an image compression encryption algorithm is proposed. Wherein, semi-tensor product compressed sensing is applied to allow data compression sampling in different dimensions resulting in reducing the data transfer load and storage cost. Subsequently, the positions and values of the image pixels are secretly altered during the algorithmic encryption process using two-dimensional cat confusion and finite field diffusion. The simulation results show that the proposed encryption algorithm effective enough to offer great encryption quality. The performance comparison analysis indicates that the proposed encryption algorithm has good furnishes better security, compression, as well as resistance to diverse data attacks.

Secure Drone Communications using MQTT protocol

With the revolutionary change in emerging technologies, the usage of drones or unmanned aerial vehicles (UAV) has exponentially increased in different sectors like Industry, healthcare, military, agriculture, real estate, manufacturing, logistics, energy and many more utilities. This rapid growth creates a concern for the secure communication between the internal communication modules and the ground based computer system used for controlling the UAV. Intruder can hack into the device and attack the internal communication device with the injection of the malicious code which can lead to the malfunction of the aircraft. Security issues related to the communication between the internal modules of the drone and the ground based computer system is of major concern and is crucial. UAVs have to operate in constrained networks with limited bandwidth. In such a constrained environment MQTT protocol can be an excellent protocol. No cryptographic techniques are used to retain the simplicity and the light weight of the MQTT protocol. This contributes for the large scope for emerging with new solutions in the protection issues of MQTT communications. This paper mainly focuses on Armstrong number encryption standard algorithm for providing a computationally simple yet a secure and strong algorithm for UAVs encryption and decryption process on the communication links using MQTT protocol.

A Modified Key Generation Algorithm to Rebalanced-RSA and RPower-RSA

The RSA cryptosystem, introduced by Rivest, Shamir, and Adleman [1], is a widely renowned public-key encryption method. Over the years, researchers have proposed numerous variants of RSA, with the goal of enhancing its efficiency by reducing computation costs in encryption or decryption processes [2]. This paper provides a comprehensive summary of the RSA algorithm and its variants, focusing on techniques aimed at improving the speed of the RSA cryptosystem. Additionally, categorizes these variants into two classes and presents two new modified key generation algorithms for the Rebalanced-RSA and the RPower-RSA. The proposed key generation algorithm improves the encryption process compared to the original variants and achieves a more balanced computing effort for both encryption and decryption.

Image retrievable encryption based on linear fitting and orthogonal transformation

Abstract With the development of cloud computing, an increasing number of resource-constrained image owners tend to store their images in the cloud and rely on image retrieval services to obtain the images they desire. However, the security of the cloud cannot be fully guaranteed. To ensure image security while achieving good retrieval performance, we have designed a retrievable image encryption algorithm based on linear fitting and orthogonal transformation. This algorithm first generates encryption and feature extraction domains through orthogonal decomposition, and then applies a modified ResNet50 network for feature extraction in the feature extraction domain. The encryption process employs an improved affine transformation based on linear fitting, where part of the fitting values comes from the original image data and the other part comes from data generated by a chaotic system. Additionally, to simplify the measurement of feature similarity in the cloud, we have designed a hierarchical feature index tree to narrow the retrieval scope, thereby reducing retrieval complexity. Experimental results show that the proposed algorithm effectively protects image privacy and achieves high retrieval accuracy. The F-score reached 6.7634% on the Ghim10k dataset and 25.514% on the Corel 1K dataset, significantly improving upon traditional methods. This algorithm has potential application value in the fields of secure image storage and efficient retrieval in the cloud.

Comparative Assessment of Hash Functions in Securing Encrypted Images

Different encryption methods have been developed to securely transmit confidential images over the Internet and combat the increasing cybercrime. Many of these methods use hash functions to enhance encryption strength. Due to the lack of a comprehensive evaluation of how different hash functions affect image encryption, this study presents a comparative analysis of the performance of various hash functions as encryption keys and analyzes their security, speed, and efficiency. The source image is first processed as a series of bytes. The bytes are divided into byte vectors, each with a length that matches the length of the hash value of a specified hash function. An XOR operation is performed between the hash value bytes and the associated byte vector. The bytes are reordered in each vector according to the ascending order of the associated hash value. Several metrics, such as Normalized Mean Absolute Error (NMAE), Peak Signal to Noise Ratio (PSNR), entropy, key size, and hash time, were used to evaluate the performance of different hash functions in image encryption. The results showed a clear variation in using various hash functions in terms of security, speed, and efficiency. With NMAE>72%, PSNR<6.62 dB, and Entropy>7.999 bpp, the use of the SHA family and MD5 is recommended in applications that need to achieve a high level of distortion in encrypted images. To resist brute-force attacks on the key, Blake2b, SHA512, and Whirlpool are the best choices with a key size of 512 bits. The Tiger is the fastest hash function, requiring the least average time of 0.372 seconds to complete the encryption process, making it the best choice for real-time applications. These findings help to choose the appropriate hash function in developing cryptographic techniques for a particular area.

Protocol-Based Synchronization of Stochastic Jumping Inertial Neural Networks Under Image Encryption Application.

This work investigates the protocol-based synchronization of inertial neural networks (INNs) with stochastic semi-Markovian jumping parameters and image encryption application. The semi-Markovian jumping process is adopted to characterize INNs under sudden complex changes. To conserve the limited available network bandwidth, an adaptive event-driven protocol (AEDP) is developed in the corresponding semi-Markovian jumping INNs (S-MJINNs), which not only reduces the amount of data transmission but also avoids the Zeno phenomenon. The objective is to construct an adaptive event-driven controller so that the drive and response systems maintain synchronous relationships. Based on the appropriate Lyapunov functional, integral inequality, and free weighting matrix, novel criteria are derived to realize the synchronization. Moreover, the desired adaptive event-driven controller is designed under a semi-Markovian jumping process. The proposed method is demonstrated through a numerical example and an image encryption process.

A novel approach for encryption and decryption of digital imaging and communications using mathematical modelling in internet of medical things

AbstractThis research introduces an innovative algorithm for the encryption and decryption of greyscale digital imaging and communications in medicine images utilizing Laplace transforms. The proposed method presents a ground breaking approach to image encryption, effectively concealing visual information and ensuring a robust, secure, and reliable encryption process. By leveraging the inherent strengths of Laplace transform, the algorithm guarantees the complete retrieval of the original image without any loss, provided the correct decryption key is used. To thoroughly evaluate the performance of the algorithm, multiple tests were conducted, including extensive statistical analyses and assessments of encryption quality. Key performance metrics were carefully measured, including correlation coefficients and entropy values, which ranged from 7.89 to 7.99. Additionally, the algorithm's effectiveness was demonstrated through peak signal‐to‐noise ratio values, which spanned from 7.597 to 9.915, indicating the degree of similarity between the original and encrypted images. Furthermore, the number of pixels change rate values, ranging from 99.519241 to 99.609375, highlighted the algorithm's ability to produce significantly different encrypted images from the original. The unified average changing intensity values, falling between 35.72345678 and 35.78233456, further underscored the algorithm's proficiency in altering pixel intensities uniformly. Overall, this research offers a significant advancement in the field of image encryption, combining theoretical robustness with practical efficiency.

Implementation of the Caesar Chiper Method in Cryptography for Message Data Security

Data security in the digital era is a very important aspect, especially in maintaining the confidentiality and integrity of information transmitted over the network. One of the classic cryptographic methods that is often used to secure messages is the Caesar Cipher. This method uses a simple substitution technique, where each letter in the message is shifted a certain number of steps in the alphabet. This research discusses the implementation of the Caesar Cipher method as a basic solution for message data security. Although this algorithm is relatively easy to implement and understand, the Caesar Cipher has weaknesses, mainly due to its fixed shifting pattern making it vulnerable to brute force attacks or frequency analysis. Through testing and implementation, this research shows how Caesar Cipher works in the encryption and decryption process, and evaluates its effectiveness in protecting messages from unauthorized access. The results show that this method, although less powerful than modern algorithms, can still be used for certain scenarios that do not require a high level of security. On the other hand, the weaknesses underscore the importance of developing and using more complex cryptographic methods to protect more sensitive information in today's digital era.

A Symmetric Reversible Audio Information Hiding Algorithm Using Matrix Embedding Within Image Carriers

To address the vulnerability of existing hiding algorithms to differential attacks and the limitations of single chaotic systems, such as small key space and low security, a novel algorithm combining audio encryption with information hiding is proposed. First, the original audio is divided into blocks to enhance efficiency. A “one-time pad” mechanism is achieved by associating the key with the plaintext, and a new multidimensional sine-coupled chaotic map is designed, which, in conjunction with multiple chaotic systems, generates the key stream. Next, the block-processed audio signals are matrix-converted and then encrypted using cyclic remainder scrambling, an improved Josephus scrambling, XOR diffusion, and bit diffusion. This results in an encrypted audio information matrix. Finally, the GHM multiwavelet transform is used to select embedding channels, and the least significant bit (LSB) method is employed to hide the information within the carrier image. The algorithm is symmetric, and decryption involves simply reversing the encryption process on the stego image. Experimental results demonstrate that the Structural Similarity Index (SSIM) between the carrier image and the stego image is 0.992540, the Peak Signal-to-Noise Ratio (PSNR) is 49.659404 dB, and the Mean Squared Error (MSE) is 0.708044. These metrics indicate high statistical similarity and indistinguishability in visual appearance. The key space of the encryption algorithm is approximately 2850, which effectively resists brute-force attacks. The energy distribution of the encrypted audio approximates noise, with information entropy close to 8, uniform histograms, high scrambling degree, strong resistance to differential attacks, and robustness against noise and cropping attacks.

Programmable Encryption Patterns from Phosphorescent Polymers Via Laser Controlling Water‐Quenching Effect

AbstractOrganic room temperature phosphorescence (RTP) from polymers holds significant promise for information encryption and anti‐counterfeiting applications. However, conventional patterning techniques limit the development of advanced RTP encryption, highlighting the need for an efficient method that achieves encryption processes quickly and conveniently. In this study, the UV laser marking machine is applied to create traceless phosphorescent patterns by leveraging the photothermal effect of the laser and the water‐absorbent quenching RTP property of polyacrylamide. A series of biaryl derivative phosphors with low π‐electron numbers are designed to limit UV absorption to below 355 nm, thereby preventing polymer sintering by the UV laser (355 nm). Additionally, two phosphorescent polymers, PB2COOH (phosphorescence lifetime τP = 2.34 s; phosphorescence quantum yield ΦP = 13.59%) and PBN (τP = 1.46 s; ΦP = 20.33%), possessing relatively excellent phosphorescent properties, are obtained. The controllable program and non‐contact processing of the marking machine enable the rapid realization of complex patterns, such as the Twelve Chinese Zodiac Signs, effectively overcoming the constraints of traditional techniques. Based on this laser technology, applications such as dual‐locking QR (quick response) codes, misleading double QR codes, labeling, and other advanced encryption methods are developed.

Feedback projection synchronization of discrete chaotic systems and its application to speech encryption

Abstract Chaotic systems are widely used in secure communication due to their sensitivity to initial values, unpredictability, and complex motion trajectories. In this paper, we study the encryption method of chaotic synchronization and introduce a scaling factor based on traditional feedback control synchronization to achieve more accurate projection synchronization. The effectiveness and robustness of the method in chaotic systems are verified through theoretical proofs and numerical simulations. A chaotic masked speech encryption system utilizing bit similarity is designed; the structural similarity index (SSIM) of the decrypted signal with the original signal is as high as 0.992866, while the SSIM value of the encrypted signal with the original signal is only 0.000030, proving the efficiency and security of the encryption process. Additionally, we analyzed the data transmission process of the encryption system. The fusion of the control signal and the encryption sequence into one transmission sequence in the channel not only saves hardware and software design resources but also reduces inter-channel interference and conflict, improving the reliability and stability of the transmission. Experimental results show that the system performs well in terms of data transmission security and anti-interference capability.