A Regulatable Data Privacy Protection Scheme for Energy Transactions Based on Consortium Blockchain

In the blockchain-based energy transaction scenario, the decentralization and transparency of the ledger will cause the users’ transaction details to be disclosed to all participants. Attackers can use data mining algorithms to obtain and analyze users’ private data, which will lead to the disclosure of transaction information. Simultaneously, it is also necessary for regulatory authorities to implement effective supervision of private data. Therefore, we propose a supervisable energy transaction data privacy protection scheme, which aims to trade off the supervision of energy transaction data by the supervisory authority and the privacy protection of transaction data. First, the concealment of the transaction amount is realized by Pedersen commitment and Bulletproof range proof. Next, the combination of ElGamal encryption and zero-knowledge proof technology ensures the authenticity of audit tickets, which allows regulators to achieve reliable supervision of the transaction privacy data without opening the commitment. Finally, the multibase decomposition method is used to improve the decryption efficiency of the supervisor. Experiments and security analysis show that the scheme can well satisfy transaction privacy and auditability.

A Cryptographic Application of the M-Injectivity of 𝑀𝑛(𝑍𝑝) Over Itself

In this paper, we present a public key scheme using Discrete Logarithm problem, proposed by Diffie and Hellman (DLP)[1], particularly known as the Computational Diffie-Hellman Problem (CDH)[12]. This paper uses the Elgamal encryption scheme [6] and extends it so that more than one message can be sent. The combination of Hill Cipher[14 ] and the property of the matrix ring 𝑴𝒏(𝒁𝒑), of being left m-injective over itself, where 𝒑 is a very large prime, are major contributions towards the proposal of this scheme.

CONFIDENTIALITY PROTECTIVE USER PROFILE MATCHING IN PUBLIC NETWORKS

We consider a scenario where a user queries a user profile database, maintained by a social networking service provider, to identify users whose profiles match the profile specified by the querying user. A typical example of this application is online dating. Most recently, an online dating website, Ashley Madison, was hacked, which results in disclosure of a large number of dating user profiles. This data breach has urged researchers to explore practical privacy protection for user profiles in a social network. Here, we propose a privacy-preserving solution for profile matching in social networks by using multiple servers. Our solution is built on homomorphic encryption and allows a user to find out matching users with the help of multiple servers without revealing to anyone the query and the queried user profiles in clear. Our solution achieves user profile privacy and user query privacy as long as at least one of the multiple servers is honest. Our experiments demonstrate that our solution is practical. KEY WORDS: User profile matching, data privacy protection, ElGamal encryption.

A Key-Based Mutual Authentication Framework for Mobile Contactless Payment System Using Authentication Server

This paper presents a framework for mutual authentication between a user device and a point of sale (POS) machine using magnetic secure transmission (MST) to prevent the wormhole attack in Samsung pay. The primary attribute of this method is authenticating the POS terminals by an authentication server to bind the generated token to a single POS machine. To secure the system from eavesdropping attack, the data transmitted between the user device and the machine is encrypted by using the Elgamal encryption method. The keys used in the method are dynamic in nature. Furthermore, comparison and security analysis are presented with previously proposed systems.

SURVEI TENTANG ALGORITMA KRIPTOGRAFI ASIMETRIS

Keamanan merupakan salah satu faktor penting dalam penyimpanan dan pengiriman data atau pesan. Salah satu cara untuk mengamankan dokumen adalah dengan menggunakan algoritma kriptografi. Kriptografi berdasarkan jenis kuncinya dibedakan menjadi dua yaitu kriptografi simetris dan asimetris. Algoritma enkripsi asimetris termasuk Rivest–Shamir–Adleman (RSA), Diffie-Hellman, Digital Secure Algorithm (DSA), XTR, Elliptic Curve Cryptography (ECC), dan Elgamal Encryption System (ESS). Dalam makalah ini akan melakukan survei paper terkait algoritma-algoritma enkripsi asimetris. Implementasi kriptografi asimetris dapat dikembangkan menggunakan algoritma-algoritma tersebut. Kata kunci : cryptography, encryption, decryption, public key