Transaction-Flow Concentration in Blockchain Networks

This dataset supports the study “Infrastructure-Aware Measurement of Transaction-Flow Concentration in Blockchain Communication Networks.” It contains processed transaction-flow data and supporting materials used to evaluate concentration patterns across heterogeneous blockchain architectures. The dataset covers Ethereum, selected Layer-2 networks including Arbitrum, Optimism, and Polygon, and Bitcoin as a UTXO-based system. The data are organized around repeated weekly observations, which are aggregated into monthly or yearly indicators depending on the analysis. For account-based systems, transaction flows are represented at the address level and, where label information is available, at the entity level. For Bitcoin, transaction-flow concentration is measured using address-level and transaction-input-level observational units, including variants that account for high-volume infrastructure-related addresses. The dataset includes normalized transaction-flow shares and concentration indicators used in the article, such as the Decentralization Index, Nakamoto coefficients, Shannon entropy, Gini coefficient, and Herfindahl-Hirschman Index. These materials enable reproduction of the empirical tables, figures, and comparative analyses reported in the study. The purpose of the dataset is to support transparency and reproducibility in the measurement of transaction-flow concentration across blockchain communication networks. It is intended for researchers studying blockchain decentralization, Layer-2 scalability, transaction routing, infrastructure concentration, resilience, censorship resistance, and network measurement.