Digital Signatures Chain and El Gamal Scheme Integration for Data Transmission Integrity in Digital Transaction

Digital signatures have been widely used by both private and government agencies. However, the use of chain digital signatures is still not widely used, especially in the military world. This results in a lack of ability to ensure data integrity, where it will be difficult to find out who has made changes to the document and to find out the original source of the document. This paper proposes a digital signature chain as a solution to guarantee data authenticity and prevent tampering during transmission. This technique involves creating a chain of digital signatures that are attached to data before it is sent over the network. The proposed method is expected to provide a more secure and efficient way to ensure data integrity, compared to traditional methods such as encryption and checksums. This paper evaluates the effectiveness of the proposed method through a series of experiments and shows that digital signature chains are an effective and reliable way to secure and maintain data transmission over networks. The proposed research aims to evaluate the effectiveness of digital signature chain technology in ensuring data security and integrity and to provide recommendations for its implementation

Modifikasi sistem kripto Elgamal hasil konstruksi Marc Joye menggunakan General Linear Group

Pada era revolusi teknologi 4.0, transformasi big data yang dikumpulkanmelalui internet pada segala bidang kehidupan (The Internet of Things)merupakan suatu keharusan. Akan tetapi internet bukanlah media komunikasiyang cukup aman karena rawan terhadap penyadapan informasi oleh pihakpihak yang tidak berhak mengakses informasi tersebut.Kriptografi merupakan salah satu bidang keilmuan untuk menjaga keamananinformasi. Salah satu sistem kripto yang masih digunakan sampai saat iniadalah sistem kripto ElGamal yang diperkenalkan oleh Taher ElGamal . Padasistem kripto ElGamal klasik dan sistem kripto modifikasi ElGamal yangdikontruksikan oleh Marc Joye, masing-masing sistem kripto ini menggunakankonsep bilangan bulat (integer). Fakta ini memotivasi suatu ide untukmenggantikan konsep bilangan bulat (integer) menjadi suatu matriks yangberukuran n n yang dinamakan dengana General Linear Group . Keunggulandari sistem kripto yang diusulkan adalah terdapat ruang plaintext yang lebihbesar dari sistem sebelumnya, sehingga ciphertext menjadi lebih acak dankeamanan pengiriman data menjadi lebih aman.Penelitian ini merupakan jenis penelitian studi literatur. Sedangkan tujuan daripenelitian ini adalah untuk memodifikasi sistem kripto ElGamal hasilkonstruksi Marc Joye menggunakan konsep General Linear Group sehinggadihasilkan suatu modifikasi sistem kripto ElGamal usulan yang lebih aman darisistem kripto ElGamal hasil konstruksi Marc Joye. Untuk itu, pada makalah inidiusulkan suatu modifikasi yang menggabungkan keunggulan dari sistem kriptoElGamal yang dikontruksikan oleh Marc Joye dan prinsip general linear grup.Hasil menunjukkan bahwa modifikasi sistem kripto ElGamal yang dihasilkanharus menggunakan general linear khusus yaitu matriks-matriks sirkulan yanginvertible atas modulo p

A Public-Key Cryptosystem Using Cyclotomic Matrices

Confidentiality and Integrity are two paramount objectives in the evaluation of information and communication technology. In this paper, we propose an arithmetic approach for designing asymmetric key cryptography. Our method is based on the formulation of cyclotomic matrices correspond to the diophantine system. The proposed cyclotomic asymmetric cryptosystem (CAC) utilizes the cyclotomic matrices, whose entries are cyclotomic numbers of order $2l^{2}$, $l$ be prime over a finite field $\mathbb{F}_{p}$ of $p$ elements. The method utilize cyclotomic matrices to design a one-way function. The outcome of a one-way function that is efficient to compute however difficult to compute its inverse unless if secret data about the trapdoor is known. We demonstrate that the encryption and decryption can be efficiently performed with asymptotic complexity of $\mathcal{O}(e^{2.373})$. Besides, we study the computational complexity of the CAC

ElGamal-type encryption for optimal dynamic quantizer in encrypted control systems

This study considers a quantizer design problem with controller encryption for minimizing performance degradation caused by encryption. It is difficult to design an optimal dynamic quantizer that converts real numbers to plaintexts for encrypted control systems with ElGamal encryption because the plaintext space of ElGamal encryption is intermittent and does not include zero and negative numbers. A variant of ElGamal encryption is proposed to apply a conventional optimal dynamic quantizer for encrypted control systems. The proposed multiplicative homomorphic cryptosystem, wherein the plaintext space is consecutive integers within a certain range, can handle zero and negative integers properly. Numerical simulations demonstrate that the optimal dynamic quantizer with the proposed cryptosystem improves the control performance of an encrypted regulator

Constant-Round Privacy Preserving Multiset Union

Privacy preserving multiset union (PPMU) protocol allows a set of parties, each with a multiset, to collaboratively compute a multiset union secretly, meaning that any information other than union is not revealed. We propose efficient PPMU protocols, using multiplicative homomorphic cryptosystem. The novelty of our protocol is to directly encrypt a polynomial by representing it by an element of an extension field. The resulting protocols consist of constant rounds and improve communication cost. We also prove the security of our protocol against malicious adversaries, in the random oracle model

Private and Oblivious Set and Multiset Operations

Privacy-preserving set operations, and set intersection in particular, are a popular research topic. Despite a large body of literature, the great majority of the available solutions are two-party protocols and are not composable. In this work we design a comprehensive suite of secure multi-party protocols for set and multiset operations that are composable, do not assume any knowledge of the sets by the parties carrying out the secure computation, and can be used for secure outsourcing. All of our protocols have communication and computation complexity of $O(m \log m)$ for sets or multisets of size $m$, which compares favorably with prior work. Furthermore, we are not aware of any results that realize composable operations. Our protocols are secure in the information theoretic sense and are designed to minimize the round complexity. Practicality of our solutions is shown through experimental results