{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T00:52:02Z","timestamp":1776300722174,"version":"3.50.1"},"reference-count":31,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2025,11,21]],"date-time":"2025-11-21T00:00:00Z","timestamp":1763683200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Executive Unit for Financing Higher Education, Research, Development and Innovation (UEFISCDI), Romania","award":["20PTE\/2025"],"award-info":[{"award-number":["20PTE\/2025"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Algorithms"],"abstract":"<jats:p>Verifiable Credentials (VCs) are a core component of decentralized identity systems, enabling individuals to prove claims without centralized intermediaries. However, managing VC revocation across segregated blockchain networks remains a key interoperability challenge. In this paper, we present a bidirectional blockchain bridge that enables the cross-chain verification of VCs between two Ethereum-compatible private blockchain networks: Geth and Besu. The system allows credentials issued and revoked on one chain to be validated from another without duplicating infrastructure or compromising security. Our architecture combines on-chain smart contracts with an off-chain relay, ensuring auditable, low-latency credential checks across chains. Our proposal is validated through an open-source working prototype. It is particularly relevant for domains where independent organizations must validate shared credentials across segregated blockchain infrastructures, including education, healthcare, and governmental identity services.<\/jats:p>","DOI":"10.3390\/a18120734","type":"journal-article","created":{"date-parts":[[2025,11,21]],"date-time":"2025-11-21T15:33:06Z","timestamp":1763739186000},"page":"734","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["A Bidirectional Bridge for Cross-Chain Revocation of Verifiable Credentials in Segregated Blockchains"],"prefix":"10.3390","volume":"18","author":[{"given":"Matei","family":"Sofronie","sequence":"first","affiliation":[{"name":"Faculty of Information Systems and Cyber Security, Military Technical Academy \u201cFerdinand I\u201d, 050141 Bucharest, Romania"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-0025-3453","authenticated-orcid":false,"given":"Andrei","family":"Br\u00eenzea","sequence":"additional","affiliation":[{"name":"Faculty of Information Systems and Cyber Security, Military Technical Academy \u201cFerdinand I\u201d, 050141 Bucharest, Romania"},{"name":"Faculty of Automatic Control and Computers, National University of Science and Technology POLITEHNICA, 060042 Bucharest, Romania"}]},{"given":"Alexandru","family":"Bratu","sequence":"additional","affiliation":[{"name":"Special Telecommunication Service, 060044 Bucharest, Romania"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-9142-730X","authenticated-orcid":false,"given":"Iulian","family":"Aciob\u0103ni\u021bei","sequence":"additional","affiliation":[{"name":"Faculty of Information Systems and Cyber Security, Military Technical Academy \u201cFerdinand I\u201d, 050141 Bucharest, Romania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4566-1545","authenticated-orcid":false,"given":"Florin","family":"Pop","sequence":"additional","affiliation":[{"name":"Faculty of Automatic Control and Computers, National University of Science and Technology POLITEHNICA, 060042 Bucharest, Romania"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Ernstberger, J., Lauinger, J., Elsheimy, F., Zhou, L., Steinhorst, S., Canetti, R., Miller, A., Gervais, A., and Song, D. 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