Paper 2026/512

Securely Scaling Autonomy: The Role of Cryptography in Future Unmanned Aircraft Systems (UAS)

William J Buchanan, Edinburgh Napier University

Rich Macfarlane, Edinburgh Napier University

Madjid Tehrani, Edinburgh Napier University

Abstract

The decentralisation of autonomous Unmanned Aircraft Systems (UAS) introduces significant challenges for 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 'Key Management' 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.

@misc{cryptoeprint:2026/512,
      author = {Paul Rochford and William J Buchanan and Rich Macfarlane and Madjid Tehrani},
      title = {Securely Scaling Autonomy: The Role of Cryptography in Future Unmanned Aircraft Systems ({UAS})},
      howpublished = {Cryptology {ePrint} Archive, Paper 2026/512},
      year = {2026},
      url = {https://eprint.iacr.org/2026/512}
}