In this paper, we propose a privacy-preserving i-voting system based on the public Stellar Blockchain network. We argue that the proposed system satisfies all requirements stated for a robust i-voting system including transparency, verifiability, and voter anonymity. The practical architecture of the system abstracts a voter from blockchain technology used underneath. To keep user privacy, we propose a privacy-first protocol that protects voter anonymity. Additionally, high throughput and low transaction fees allow handling large scale voting at low costs. As a result we built an open-source, cheap, and secure system for i-voting that uses public blockchain, where everyone can participate and verify the election process without the need to trust a central authority. The main contribution to the field is a method based on a blind signature used to construct reliable voting protocol. The proposed method fulfills all requirements defined for i-voting systems, which is challenging to achieve altogether.

This paper proposes an improved monitoring and measuring system dedicated to industrial infrastructure. Our model achieves security of data by incorporating cryptographical methods and near real-time access by the use of virtual tree structure over records. The currently available blockchain networks are not very well adapted to tasks related to the continuous monitoring of the parameters of industrial installations. In the database systems delivered by default (the so-called world state), only the resultant or the last value recorded by the IoT device is stored. Effective use of measurement values recorded in the past requires each time viewing the entire chain of recorded events for a given IoT device. The solution proposed in the article introduces the concept of dependent wallets, the purpose of which is the aggregation and indexation of changes in machine parameters, recorded in the original wallets. As a result, we can easily get data from a certain sensor or sensors in the specified date range, even if the chain of transactions is very long. Our contribution is a universal mechanism that improves the efficiency of the infrastructure monitoring process, which uses blockchains to record measurements from sensors. The proposed model has been experimentally tested on two types of blockchains: Stellar and Hyperledger Fabric.

Lawyers, laboratories, auditors, and banks often need access to sensitive personal data to provide services such as genetic testing, paternity testing, STD testing, credit scoring, or legal advice. Processing such data exposes both service providers (SPs) and users to privacy risks: SPs risk violating laws like the General Data Protection Regulation (GDPR) and the Consumer Protection Act (CPA), while users risk losing their privacy. We observe that personal data is often only needed for logistical purposes like payment or communication and could be provided anonymously if suitable methods existed. To address this, we present a solution that enables services to be delivered without collecting personal data. Our protocol combines anonymous payment methods (e.g., cash, privacy-preserving cryptocurrencies), blockchain for fairness, and distributed content-addressable storage networks to deliver results. Compared to existing approaches, our protocol achieves anonymity under weaker assumptions, supports the transfer of physical materials and conflict resolution, and eliminates the need for customer interaction with a trusted arbiter in conflict-free cases-making it more practical. We analyze the protocol’s fairness and implement a prototype using Ethereum as a message board, Monero for anonymous payments, and Powergate (IPFS/Filecoin) as a decentralized storage solution.

Lawyers, laboratories, auditors or banks often need data containing sensitive personal information to provide their services. Examples of sensitive services include genetic testing, paternity testing, STD testing, credit scoring or legal advice. The processing of personal data, especially when providing services involving sensitive data such as health records, biological material or legal documents, exposes both users and service providers (SPs) to privacy risks. SPs are at risk of violating GDPR, CPAA and other legal regulations, while customers are at risk of losing their privacy. We observe that personal data is often only used for logistical purposes, such as payment or communication, and could be provided anonymously if such methods were available. We present a solution that allows services to be provided without collecting personal data. We use anonymous payment methods such as cash and anonymous cryptocurrencies, blockchain to achieve fairness, and distributed content-addressable storage networks to deliver results. Compared to other solutions, our protocol achieves anonymity with weaker assumptions, supports physical materials and conflict resolution, and does not require the customer to interact with the blockchain in conflict-free transactions, demonstrating better practicality. In this work, we analyse the fairness of our protocol and implement it using Ethereum technology as a message board, Monero as an anonymous payment method, and Powergate (IPFS and Filecoin) as a decentralised storage network.

Voting is a cornerstone of collective participatory decision-making in contexts ranging from political elections to decentralized autonomous organizations (DAOs). Despite the proliferation of internet voting protocols promising enhanced accessibility and efficiency, their evaluation and comparison are complicated by a lack of standardized criteria and unified definitions of security and maturity. Furthermore, socio-technical requirements by decision makers are not structurally taken into consideration when comparing internet voting systems. This paper addresses this gap by introducing a trust-centric maturity scoring framework to quantify the security and maturity of seventeen internet voting systems. A comprehensive trust model analysis is conducted for selected internet voting protocols, examining their security properties, trust assumptions, technical complexity, and practical usability. In this paper we propose the Internet Voting Maturity Framework (IVMF) which supports nuanced assessment that reflects real-world deployment concerns and aids decision-makers in selecting appropriate systems tailored to their specific use-case requirements. The framework is general enough to be applied to other systems, where the aspects of decentralization, trust, and security are crucial, such as digital identity, Ethereum layer-two scaling solutions, and federated data infrastructures. Its objective is to provide an extendable toolkit for policy makers and technology experts alike that normalizes technical and non-technical requirements on a univariate scale.