ElGamal Research Articles

BPA: A decentralized payment system that balances privacy and auditability

<abstract><p>The rapid development of blockchain transactions highlights the importance of privacy protection (including anonymity and confidentiality) and underscores the necessity for auditability. Some schemes, such as PGC and Miniledger, support privacy protection and auditability. However, they only offer incomplete privacy protection (i.e., supporting anonymity or confidentiality exclusively). In response to these issues, we propose a scheme that achieves partial anonymity, confidentiality, auditability, and traceability. By integrating a variant of Pedersen commitments and randomizable signatures, we achieve partial anonymity for users and the auditability of transactions, thereby protecting user privacy under audit conditions. Based on the twisted ElGamal encryption algorithm and specially constructed zero-knowledge proofs, we achieve confidentiality of transaction amounts under legal and regulatory conditions. System test results indicate that this scheme effectively meets the above requirements. The feasibility of this scheme is confirmed through system testing, comparative analysis, and security analysis.</p></abstract>

Image encryption with leveraging blockchain-based optimal deep learning for Secure Disease Detection and Classification in a smart healthcare environment

<abstract> <p>Blockchain (BC) in healthcare can be used for sharing medical records and secure storage and other confidential data. Deep learning (DL) assists in disease recognition through image analysis, specifically in detecting medical conditions from images. Image encryption ensures the security and privacy of medical images by encrypting the image before sharing or storage. The combination of image encryption, BC, and DL provides an efficient and secure system for medical image analysis and disease detection in healthcare. Therefore, we designed a new BC with an Image Encryption-based Optimal DL for Secure Disease Detection and Classification (BIEODL-SDDC) technique. The presented BIEODL-SDDC technique enables the secure sharing of medical images via encryption and BC technology with a DL-based disease classification process. Furthermore, the medical image encryption process took place using the ElGamal Encryption technique with a giraffe kicking optimization (GKO) algorithm-based key generation process. In addition, BC-based smart contracts (SCs) were used for the secure sharing of medical images. For the disease detection process, the BIEODL-SDDC technique encompassed EfficientNet-B7-CBAM-based feature extraction, Adam optimizer, and a fully connected neural network (FCNN). The experimental validation of the BIEODL-SDDC technique was tested on medical image datasets and the outcome highlighted an enhanced accuracy outcome of 94.81% over other techniques.</p> </abstract>

Confidential Transaction Balance Verification by the Net Using Non-Interactive Zero-Knowledge Proofs

One of the main trends for the monitoring and control of business processes is to implement these processes via private blockchain systems. These systems must ensure data privacy and verifiability for the entire network here denoted by ‘Net’. In addition, every business activity should be declared to a trusted third party (TTP), such as an Audit Authority (AA), for tax declaration and collection purposes. We present a solution for a confidential and verifiable realization of transactions based on the Unspent Transaction Output (UTxO) paradigm. This means that the total sum of transaction inputs (incomes) $In$ must be equal to the total sum of transaction outputs (expenses) $Ex$, satisfying the balance equation $In=Ex$. Privacy in a private blockchain must be achieved through the encryption of actual transaction values. However, it is crucial that all participants in the network be able to verify the validity of the transaction balance equation. This poses a challenge with probabilistically encrypted data. Moreover, the inputs and outputs are encrypted with different public keys. With the introduction of the AA, the number of different public keys for encryption can be reduced to two. Incomes are encrypted with the Receiver’s public key and expenses with the AA’s public key. The novelty of our realization lies in taking additively-multiplicative, homomorphic ElGamal encryption and integrating it with a proposed paradigm of modified Schnorr identification providing a non-interactive zero-knowledge proof (NIZKP) using a cryptographically secure h-function. Introducing the AA as a structural element in a blockchain system based on the UTxO enables effective verification of encrypted transaction data for the Net. This is possible because the proposed NIZKP is able to prove the equivalency of two ciphertexts encrypted with two different public keys and different actors. This integration allows all users on the Net to check the UTxO-based transaction balance equation on encrypted data. The security considerations of the proposed solution are presented.

The tropical version of El Gamal Encryption

In this paper, we consider the new version of tropical cryptography protocol, i.e the tropical version of El Gamal encryption. We follow the ideas and modify the clasical El Gamal encryption using tropical matrices and matrix power in tropical algebra. Then we also provide a toy example for the reader’s understanding.

Privacy-Preserving Cross-Silo Federated Learning Atop Blockchain for IoT

Cross-silo federated learning (FL) is promising in facilitating data collaboration across various organizations, which greatly alleviates the information silo problem in industries and promotes the data intelligence of internet of things. With the advances of decentralized FL, the higher requirements of trust and privacy are put forward. Traditional FL heavily relies on a central coordinating server, which suffers from single points of failure and lacks trust in the correctness of aggregation results. What’s more, the intrinsic privacy issues of FL have aroused public attention, such as gradient inversion attack in local gradients. However, the privacy of quantized gradients remains serious and lacks attention, especially the most extremely 1-bit quantization in sign-based FL. In this paper, we demonstrate the potential privacy risk in sign-based FL by presenting a new gradient inversion attack, which successfully restores the original data from sign-based quantized gradients. And then we tackle the above two challenges via constructing a self-aggregation privacy-preserving federated learning atop blockchain, which takes advantage of a variant of ElGamal encryption to protect the privacy of local sign-based quantized gradients, and leverages the smart contract to achieve secure self-aggregation for participants without involving a centralized server. Moreover, we analyze that the proposed protocol achieves privacy and public verifiability. Finally, we evaluate the performance of the proposed protocol with a real deep learning model, and the results show that our protocol is resilient against gradient inversion attack in a decentralized environment without sacrificing learning accuracy.

A Practical Multiparty Private Set Intersection Protocol Based on Bloom Filters for Unbalanced Scenarios

Multiparty Private Set Intersection (MPSI) is dedicated to finding the intersection of datasets of multiple participants without disclosing any other information. Although many MPSI protocols have been presented, there are still some important practical scenarios that require in-depth consideration such as an unbalanced scenario, where the server’s dataset is much larger than the clients’ datasets, and in cases where the number of participants is large. This paper proposes a practical MPSI protocol for unbalanced scenarios. The protocol uses the Bloom filter, an efficient data structure, and the ElGamal encryption algorithm to reduce the computation of clients and the server; adopts randomization technology to solve the encryption problem of the 0s in the Bloom filter; and introduces the idea of the Shamir threshold secret-sharing scheme to adapt to multiple environments. A formal security proof and three detailed experiments are given. The results of the experiments showed that the new protocol is very suitable for unbalanced scenarios with a large number of participants, and it has a significant improvement in efficiency compared with the typical related protocol (TIFS 2022).

Comparing the RSA and elgamal encryption methods

In the realm of computer science, the speed and efficiency of data processing vary depending on the chosen algorithms and programming languages. This article delves into an exploration of which combinations can yield the highest overall performance. Starting with an introduction to the selected algorithms and languages, the underlying mathematical foundations and principles of each algorithm are presented. The research then shifts its focus to the practical aspect translating these algorithms into executable code. Three specific combinations are tested: RSA algorithm implemented in Python, Elgamal algorithm implemented in Python, and RSA algorithm executed in C++. To ensure reliable results, each combination underwent 30 test iterations, with empirical data subsequently gathered. Two primary comparisons were conducted: the first pitting the Python-based RSA against the Python-based Elgamal, and the second contrasting the Python-based RSA with its C++ counterpart. From these tests, a compelling conclusion emerges. When it comes to transmitting encrypted messages and subsequently decrypting them, the RSA algorithm paired with Python emerges as the most optimal choice. Readers will gain a deeper understanding of the strengths and potential limitations of each pairing, equipping them to make more informed decisions in their cryptographic endeavors.

Lightweight authentication scheme based on Elliptic Curve El Gamal

ABSTRACT Elliptic Curve Cryptography (ECC) is a promising cryptosystem as it presents the ideal choice for implementing public-key cryptography in resource-limited devices, such as those found in envisioned Internet of Things applications, e.g. wireless sensors. Elliptic Curve ElGamal (ECEG) is a renowned member of the ECC family. However, it requires encoding the message before encryption and decoding it after decryption. To better improve the processing time and to avoid sharing a lookup table, we propose, in this document, a new method that exchanges encoding parameters and authenticates endpoints at the same time. So, our new protocol ensures the authentication of communication parties and integrity of ephemeral encoding parameters. The robustness of our solution is proven by the Scyther tool. Experimental tests have been carried out, and the performance of the new methods is provided and compared with RSA and related work. Security and performance analysis show that our new scheme has achieved improved functionality and higher security while maintaining low computational.

Decentralized universally verifiable stake voting system with perfect privacy

Stake voting is a voting system where the vote cast by a voter is proportional to their account balance/asset. We propose the first implementation of an efficient, fully-decentralized, universally-verifiable stake voting system with perfect voter privacy. Our contribution is two-fold. First, we design a zero knowledge proof (ZKP) for equality of plaintexts of 2 different ciphertexts encrypted under different encryption schemes, one under ElGamal encryption scheme and another under Paillier encryption scheme. We believe that ours is the first ZKP design for this problem statement. Second, we implement a publicly-verifiable Stake voting system using the ZKP design by enforcing perfect privacy to voters and correctness of election results. Our voting system is applicable to many situations like shareholder/stockholder voting in companies. We have also provided the financial and computational breakdown feasibility of our implementation on Ganache local blockchain.

COMPARATIVE STUDY OF ELGAMAL AND LUC ALGORITHM IN CRYPTOGRAPHIC KEY GENERATION

In today’s era of digital, data security in communication channel becomes important factor to be considered during exchange of information. Cryptography is one of techniques to send and receive information securely through an insecure channel. Based on the number of keys used, encryption methods are categorized as symmetric and asymmetric cryptography. Compared to symmetric cryptography that often suffers from key management issues, asymmetric cryptography delivers higher level of data security. Thus, asymmetric cryptography is more preferred when security if the priority. To determine suitable algorithm, three essential aspects should be considered: security, speed, and prime numbers. This study aims to compare the application of asymmetric cryptographic algorithms between ElGamal and LUC algorithms in the key generation process. A comparative analysis of these two algorithms was conducted by evaluating the processing speed and prime numbers during key generation process to determine the advantages and drawbacks from ElGamal and LUC algorithms. The application in this study was developed using PHP programming language by following the Waterfall Model. Application testing involved two kinds of tests: (i) Black Box test and (ii) System Usability Scale (SUS) test. Results show the application developed from this study successfully performed the encryption, decryption, and checking of prime numbers from ElGamal and LUC algorithms. It displayed ciphertext, plaintext, and the speed of the encryption and decryption process from both methods. The black box test showed that all application functions follow the user's needs, while System Usability Scale (SUS) test obtained an average score of SUS interpretation of 83.75. This value means the adjective ratings was “excellent”, the grade scale was “B”, and the acceptability range was “acceptable”. It is concluded that the LUC algorithm superior to ElGamal in terms of the speed of encryption process. However, during the decryption process the LUC algorithm responded slower than ElGamal.

Digital Signature Security Analysis By Applying The Elgamal Algorithm And The Idea Method

The development of an all-digital era, all activities use digital technology. Including signatures, hands are no longer manual now, signatures can be modified digitally. The application of digital signatures can be used to allow for document authenticity issues. The signature combines two methods namely Elgamal Algorithm and IDEA. The Elgamal algorithm is used to encrypt and decrypt signatures. The IDEA algorithm is used to strengthen signatures so that others don't modify them. The signature process begins with generating the public and private keys. The process of generating public keys (p,q,g,y) and private keys. With the signature of a binary document that is given by the sender to the recipient, the authenticity of the contents of the file, the identity of the sender, and the files that have been received by the recipient can be guaranteed. Affixing a digital signature is done by encrypting it with the sender's private key. In this way, checking the authenticity of documents and senders can be done.

Penggabungan Metode Vigènere Cipher dan ElGamal Pada Pengamanan Pesan Rahasia

Vigènere Cipher is a symmetric cryptographic algorithm that uses the same type of key in the encryption and decryption process. The security of the Vigènere Cipher method lies in the modulo calculation used. ElGamal is an asymmetric cryptographic algorithm that uses two different types of keys in the encryption and decryption process. The security of the ElGamal algorithm lies in the complexity of calculating large prime numbers. The Vigènere Cipher and ElGamal have their advantages and disadvantages. The researchers are interested in combining the advantages of the two methods. In this study, two locks were carried out in the encryption and decryption process. The encryption process uses a public key and the decryption process uses a public key and a secret key . The key used comes from key formation using the ElGamal algorithm. The key security formed from the ElGamal algorithm lies in the large prime , the primitive root of the prime number , and the random integer which comes from the last three digits of Student Number. The conclusion of this study is that the combination of the Vigènere Cipher and ElGamal methods can increase the security of secret messages because it produces a ciphertext with twice the size ) of the original message.

PSI-CA-Based Vehicle Selection Scheme for Data Sharing in Internet of Vehicles

In recent years, the development of the Internet of Vehicles (IoV) has led to an increase in the demand for data sharing services for the IoV. In the era of big data, safe and convenient data sharing services for IoV are inseparable from the support of reliable data. With the increase in the number of smart cars, how to filter the data provided by vehicles while protecting privacy to improve the quality of data sharing services has attracted the attention of scholars. However, in the existing data sharing scheme for IoV, the vehicles that provide data are selected based on the reputation mechanism or the voting mechanism. Our analysis shows that these two mechanisms lack objectivity and are vulnerable to cooperative attack. Therefore, based on spatiotemporal matching, a new trusted relationship establishment method, this paper proposes an objective and cooperative attack-resistant vehicle selection scheme for data sharing in IoV. Bloom filters and an exponential ElGamal encryption scheme are used to implement private set intersection cardinality (PSI-CA) technology for evaluating spatiotemporal matching level. In this paper, the scheme proposed is of great significance to improve existing vehicle services and improve driving safety.

Implementasi Penyisipan Pesan Teks Terenkripsi Menggunakan Kriptografi ElGamal pada Citra Digital Menggunakan Steganogarafi LSB

Message security is very important in maintaining the confidentiality of information, especially those containing important information whose contents should only be known by the entitled party. Therefore, security is needed for messages that are confidential so that messages cannot be intercepted by people who do not want them and the information content of the message becomes more secure. One way is to apply ElGamal and LSB cryptography methods to be able to provide security to text messages by inserting into digital images, the ElGamal algorithm focuses on the strength of the key in solving discrete logarithm problems. By utilizing large prime numbers and discrete logarithm problems which are quite difficult and also by applying the LSB method for text insertion, the security of the key is more guaranteed. The test results on five image objects with the .BMP extension on the application that was built were running well and correctly. The image that is inserted in the encryption process is the insertion of text in the image after it is decrypted and the image produced after the encryption and decryption process is no different from the original image and the same thing for the image size does not change

Applying Detection Leakage on Hybrid Cryptography to Secure Transaction Information in E-Commerce Apps

Technology advancements have driven a boost in electronic commerce use in the present day due to an increase in demand processes, regardless of whether goods, products, services, or payments are being bought or sold. Various goods are purchased and sold online by merchants (M)s for large amounts of money. Nonetheless, during the transmission of information via electronic commerce, Ms’ information may be compromised or attacked. In order to enhance the security of e-commerce transaction data, particularly sensitive M information, we have devised a protocol that combines the Fernet (FER) algorithm with the ElGamal (ELG) algorithm. Additionally, we have integrated data leakage detection (DLD) technology to verify the integrity of keys, encryptions, and decryptions. The integration of these algorithms ensures that electronic-commerce transactions are both highly secure and efficiently processed. Our analysis of the protocol’s security and performance indicates that it outperforms the algorithms used in previous studies, providing superior levels of security and performance.

Cryptographic Method to Enhance the Data Security using ElGamal Algorithm and Sumudu Transform

Abstract: Cryptography is the science of using mathematics to encrypt and decrypt data. Cryptography includes two phases: Encryption and Decryption. Encryption is the process of transforming plaintext to ciphertext, whereas decryption is the reverse procedure. Encryption and decryption schemes based on Sumudu Transform are unable to give more security while communicating the information. ElGamal is a public key algorithm that is based on the discrete logarithm problem. The purpose of this study is to introduce a cryptographic method that uses the ElGamal algorithm and Sumudu Transform to improve communication security.

A User Authentication Schema Under the Integration of Mobile Edge Computing and Blockchain Technology

The safe and efficient authentication of users is the basis for the realization of the Internet of Things. A reliable and fast user authentication schema that combines mobile edge computing and blockchain technology is proposed. This schema adopts the polling hosting method to optimize the practical Byzantine Fault Tolerance (PBFT) algorithm, it reduces the impact of tokens in the algorithm, and ensures trusted authentication. The two-way authentication protocol between the cluster head and the base station, and the one-way authentication protocol between the base station and the sensor node are designed to effectively simplify the authentication process of sensor nodes, which further guarantees the security and speed of user authentication and effectively meets the security, reliability, and convenience requirements of the Internet of Things. Simulation experiments show that the schema can achieve efficient information verification, and the identity authentication time and protocol authentication times are only 23.58 ms and 25.06 ms, respectively, which has obvious performance advantages over the Paillier algorithm, the hybrid Paillier-blowfish algorithm, and the ElGamal algorithm.

Privacy-Preserving Biometrics Image Encryption and Digital Signature Technique Using Arnold and ElGamal

The scientific study of privacy-preserving biometrics, represented by the palmprint, face, and iris, has grown tremendously. That being said, there has not been much attention paid to the proper preservation, transmission, and authentication of biometric images used in everyday applications. In this paper, we propose a new complete model for encrypting and decrypting biometric images, including their signing and authentication, using a nested algorithm of 3D Arnold Transform. In addition, the ElGamal Encryption Algorithm for the encryption part and the ElGamal Digital Signature for the signature part are applied. The model is mainly based on the Arnold Transform and Public-Key Cryptosystem, which are convenient for key transfer and fully functional. Here, the model succeeds in encrypting and securing the authentication process for privacy-preserving biometric images. Various tests have been carried out to demonstrate the feasibility and security of the proposed model and have been compared with existing encryption methods to achieve better results. Moreover, the proposed model can also be extended to the storage, transmission, and authentication of biometric data for daily use.

The power-generalized k-Horadam sequences in different modules and a new cryptographic method with these sequences

In this study, unlike other power sequences, we define new ones in the integer and integer-valued polynomial module. We call these sequences the power-generalized [Formula: see text]-Horadam sequence in the integer module and the power-generalized [Formula: see text]-Horadam sequence in the integer-valued polynomial module. Using these sequences, we rebuild the ElGamal cryptosystem and then obtain a new cryptographic method by combining this and symmetric systems. We provide an encryption example where our method is applied. Finally, we see the advantages of the new cryptographic method when we compare the obtained new cryptographic method with some of the asymmetric cryptographic systems such as RSA and ElGamal. And we achieve that new cryptographic method that has more advantageous.

A PUBLIC KEY ENCRYPTION - AUTHENTICATION SCHEME BASED ON ELGAMAL CRYPTOGRAPHIC ALGORITHM

The article proposes a public-key cryptographic scheme based on the ElGamal algorithm. This scheme can perform security functions and authenticate the origin and integrity of the encrypted message simultaneously. Moreover, the proposed scheme is also used as the basis for developing an algorithm to establish a shared secret key for symmetric key cryptosystems.