{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T11:03:35Z","timestamp":1774350215831,"version":"3.50.1"},"reference-count":30,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,3,20]],"date-time":"2026-03-20T00:00:00Z","timestamp":1773964800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cryptography"],"abstract":"<jats:p>The decentralisation of autonomous Unmanned Aircraft Systems (UASs) introduces significant challenges in terms of establishing secure communication and consensus in contested, resource-constrained environments. This research addresses these challenges by conducting a comprehensive performance evaluation of two cryptographic technologies: Messaging Layer Security (MLS) for group key exchange, and threshold signatures (FROST and BLS) for decentralised consensus. Seven leading open-source libraries were methodically assessed through a series of static, network-simulated, and novel bulk-signing benchmarks to measure their computational efficiency and practical resilience. This paper confirms that MLS is a viable solution, capable of supporting the group sizes and throughput requirements of a UAS swarm. It corroborates prior work by identifying the Cisco MLSpp library as unsuitable for dynamic environments due to poorly scaling group management functions, while demonstrating that OpenMLS is a highly performant and scalable alternative. Furthermore, the findings show that operating MLS in a \u2018key management\u2019 mode offers a dramatic increase in performance and resilience, a critical trade-off for UAS operations. For consensus, the benchmarks reveal a range of compromises for developers to consider, while identifying the Zcash FROST implementation as the most effective all-around performer for sustained, high-volume use cases due to its balance of security features and efficient verification.<\/jats:p>","DOI":"10.3390\/cryptography10020020","type":"journal-article","created":{"date-parts":[[2026,3,20]],"date-time":"2026-03-20T17:02:43Z","timestamp":1774026163000},"page":"20","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Securely Scaling Autonomy: The Role of Cryptography in Future Unmanned Aircraft Systems (UASs)"],"prefix":"10.3390","volume":"10","author":[{"given":"Paul","family":"Rochford","sequence":"first","affiliation":[{"name":"Blockpass ID Lab, Edinburgh Napier University, Edinburgh EH10 5DT, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0809-3523","authenticated-orcid":false,"given":"William J.","family":"Buchanan","sequence":"additional","affiliation":[{"name":"Blockpass ID Lab, Edinburgh Napier University, Edinburgh EH10 5DT, UK"}]},{"given":"Rich","family":"Macfarlane","sequence":"additional","affiliation":[{"name":"Blockpass ID Lab, Edinburgh Napier University, Edinburgh EH10 5DT, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4838-5865","authenticated-orcid":false,"given":"Madjid","family":"Tehrani","sequence":"additional","affiliation":[{"name":"Blockpass ID Lab, Edinburgh Napier University, Edinburgh EH10 5DT, UK"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8550","DOI":"10.1109\/TAES.2023.3307092","article-title":"Group Secret Key Generation Using Physical Layer Security for UAV Swarm Communications","volume":"59","author":"Jangsher","year":"2023","journal-title":"IEEE Trans. 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