Smart contract-based secure cooperative spectrum sensing algorithm

Spectrum sensing is the key technology of cognitive radio. In this article, we apply blockchain technology in spectrum sensing process and propose a related algorithm based on reputation. The algorithm builds a system model based on smart contract in blockchain and applies blockchain asymmetric encryption algorithm and digital signature technology in the process of secondary users’ transmitting local judgments to the secondary user base station. The algorithm can resist spectrum sensing data falsification (SSDF) attack launched by malicious users. This article comprehensively considers the channel error rate, detection probability, secondary user base station budget and remaining energy of the secondary users (SUs) and then establishes the SU’s utility function as well as the game model. By solving the Nash equilibrium, the SU determines whether it uploads sensing data. Finally, the SU base station selects registered SUs by calculating and updating their reputation, obtaining the final judgment by voting rule. With simulations, we prove that the algorithm proposed in this article increases the accuracy and security of spectrum sensing and can effectively resist SSDF attack.

ETHERST: Ethereum-Based Public Key Infrastructure Identity Management with a Reward-and-Punishment Mechanism

Public Key Infrastructure (PKI) is the fundamental of secure digital communications. It provides a secure means to authenticate identities over the Internet. Symmetric or asymmetric encryption schemes are widely used in identity authentication in any kind of PKI. The conventional PKI has several drawbacks due to the centralized and non-transparent design. Several recent research works utilize blockchain technology to overcome the limitations of conventional implementations of PKI. Blockchain-based PKI integrates blockchain technology with PKI to form a new type of decentralized PKI (DPKI). Several works utilize the currency property in blockchains to implement the reward-and-punishment mechanism. In this paper, we propose a smart contract-based PKI which utilizes the Ethereum smart contract to build a new type of blockchain-based PKI with the reward-and-punishment mechanism using ERC-20 tokens. It has several advantages over previous implementations of similar research that use Ethereum’s main currency—Ether.

Analysis of the possibility of using modern packages of computer algebra in the synthesis of crypto-primitives

The paper deals with systems of computer algebra - software for symbolic calculations, which allows to conduct the entire cycle of development of a mathematical model. The paper presents the results of the analysis of systems of computer algebra with specialized purpose Magma, evaluation of the possibility of its use for modulation of processes in symmetric and asymmetric cryptographic systems, as well as recommendations for their further improvement. Magma functionality is also analyzed for evaluation of possibility to model and study promising candidates for the post-quantum standard of electronic signature algorithms, asymmetric encryption and key encapsulation, including algorithms based on cryptographic transformations in the lattice-based, the use of hash trees, mathematical codes that are undergoing research during the NIST PQC competition, as well as the draft standard "Vershina 1".

Ballot secrecy: Security definition, sufficient conditions, and analysis of Helios

We propose a definition of ballot secrecy as an indistinguishability game in the computational model of cryptography. Our definition improves upon earlier definitions to ensure ballot secrecy is preserved in the presence of an adversary that controls ballot collection. We also propose a definition of ballot independence as an adaptation of an indistinguishability game for asymmetric encryption. We prove relations between our definitions. In particular, we prove ballot independence is sufficient for ballot secrecy in voting systems with zero-knowledge tallying proofs. Moreover, we prove that building systems from non-malleable asymmetric encryption schemes suffices for ballot secrecy, thereby eliminating the expense of ballot-secrecy proofs for a class of encryption-based voting systems. We demonstrate applicability of our results by analysing the Helios voting system and its mixnet variant. Our analysis reveals that Helios does not satisfy ballot secrecy in the presence of an adversary that controls ballot collection. The vulnerability cannot be detected by earlier definitions of ballot secrecy, because they do not consider such adversaries. We adopt non-malleable ballots as a fix and prove that the fixed system satisfies ballot secrecy.

Compact Spiral Asymmetric encryption Distributed Ledger –Secured and authentication Mobile Payment System in Higher Institutions

Looking at the higher learning institutions, there is no question that the current methods for paying student fees are inefficient, inconvenient, and wasteful of time. In addition, the rise in the number of students studying in higher learning institutions has led to long frustrating queues and overcrowding in most financial institutions during payment of student fees. This paper sought to design and implement a secure block chain-based payment system for higher learning institutions in developing countries. Students are to use the proposed payment system to pay tuition fees and other student fees to their respective higher educational institution. In addition, students are to use the proposed payment to pay for goods and services provided by the institution and other merchants in the institution’s premises. In this study, object oriented software development methodology was used to implement the proposed payment system. The proposed system consists of a mobile e-wallet, RESTful API, and blockchain as the core component of the API.

An improved NFC device authentication protocol

Aimed at the security authentication problem between Near Field Communication (NFC) devices, this paper uses the technology of asymmetric encryption algorithm, symmetric encryption algorithm, hash function, timestamp and survival period to improve the confidentiality, performance and security of the protocol. The symmetric encryption algorithm encrypts the transmission content, while the asymmetric encryption algorithm encrypts the shared key. The whole authentication process is secure, and the key distribution is secure. The improved NFC device authentication protocol can effectively resist the brute force attack, man-in-the-middle attack and replay attack in the authentication process, it can reduce the number of message transmission in the authentication process, improve the transmission efficiency, enhance the confidentiality, integrity, non-repudiation and improve the security of NFC device authentication.

A Cross-Border E-Commerce Approach Based on Blockchain Technology

In the current cross-border electronic commerce (e-commerce) system, various document recording and authorization processes are cumbersome, record sharing efficiency is low, and identity verification is difficult. A method of asymmetric encryption technology combining Blockchain technology and cryptography is proposed. The advantages of asymmetric encrypted communications include high security and ease of multiparties communication collaboration, being applied to a peer-to-peer network formed by Blockchain technology, and making cross-border e-commerce record cross-domain sharing traceable, data immutable, and identity verification simplified. First of all, based on the immutable modification of Blockchain technology and asymmetric encryption technology, file synchronization contracts and authorization contracts are designed. Its distributed storage advantages ensure the privacy of users’ cross-border e-commerce information. Second, the design of the cross-domain acquisition contract can effectively verify the identity and transmission efficiency of both parties to the data sharing, so that illegal users can be safely filtered without a third-party notary institution. The simulation experiment results show that the solution proposed in this paper has obvious advantages in data antitheft, multiparty authentication, and saving system overhead compared with traditional cloud computing methods to solve the problem of sharing medical records. It provides a reference for solving the security problems in the process of data sharing by using the advantages of Blockchain’s decentralization and auditability and provides reference ideas for solving the problems of data sharing and cross-domain authentication.

State of development, research and standardization of cryptographic transformations such as asymmetric encryption and post-quantum key encapsulation protocol

The paper presents the state of development of cryptocurrencies such as ACS and PIC at the international and national levels. The state of standardization of cryptocurrencies of ASS and PIK at the international competition NIST of the USA, the requirements put forward to candidates on 2 and 3 rounds of competition are considered. The state of standardization of crypto transformations of this type at the national level in Ukraine is considered, and a brief description of the national standard ASSH DSTU 8961: 2019, based on algebraic lattices, is given. The methodology and results of achieving the national standard DSTU 8961:2019 against attacks by third-party channels in terms of the dependence of the time of direct and reverse transformation (encapsulation and decapsulation of the key) on the number of units in the private key.