ELA: zero-touch IoT enrollment, standardized at the IETF

Jun 11, 2025 · 2 min read
ELA — Lightweight Authorization over EDHOC.

What it is

ELA (Lightweight Authorization over EDHOC) is an IETF draft for the zero-touch enrollment of IoT devices: provisioning a freshly-shipped device with operator credentials, without manual configuration or pre-shared secrets. ELA is a 3-message protocol that piggybacks on EDHOC (RFC 9528), adding lightweight authorization between a device, a gateway, and an enrollment server. It’s being standardized in the IETF LAKE working group.

What I built

I am co-author of the IETF draft draft-ietf-lake-authz and built the reference implementation:

  • Co-design the protocol with Göran Selander (Ericsson) and Mališa Vučinić (Inria), iterating with the LAKE working group across multiple drafts and meetings
  • Reference implementation on top of Lakers (Rust + Python + C bindings)
  • Working demos: 1-gateway enrollment with DotBots; multi-gateway enrollment integrated with Mari
  • Performance evaluation vs. EAP-EDHOC over both BLE and SmartMesh-IP
  • Author of the conference and journal papers
  • Presented draft updates and demos at IETF 118 (Prague), 119 (Brisbane, remote), 120 (Vancouver), 122 (Bangkok), 123 (Madrid), and several LAKE interim meetings

Why it’s hard

  • IoT devices need to bootstrap trust with an operator they have no prior relationship with — and at scale
  • Existing approaches (EAP-EDHOC, EAP-NOOB, manual provisioning) require many round trips, special hardware, or human steps
  • Privacy: how does a device advertise “I support ELA” without leaking its identity to nearby observers?
  • Crypto budget: piggybacking on EDHOC means staying within EDHOC’s tight message limits
  • Standardization is itself a multi-year coordination problem with stakeholders across vendors, academia, and IETF working groups

Numbers

  • 3 messages end-to-end (vs. 9 for EAP-EDHOC)
  • ~60% faster handshake than EAP-EDHOC over SmartMesh-IP (averaged over 100 runs)
  • ~46 bytes smaller per handshake than EAP-EDHOC
  • Demoed at IETF 119, 120, 122, 123
  • Multiple working-group versions submitted (-01 in Mar 2024, -02 in Jul 2024, and beyond)
  • Integrated into Mari at the IETF 123 hackathon — first BLE-based zero-touch swarm enrollment

Publications

  • ELA: Secure, Lightweight, and Zero-Touch Enrollment for IoT Devices. G. Fedrecheski, G. Selander, T. Watteyne, M. Vučinić. Elsevier Computer Networks (COMNET), 2026. [Link]
  • ELA: Secure, Lightweight, and Zero-Touch Enrollment for IoT Devices. G. Fedrecheski, G. Selander, T. Watteyne, M. Vučinić. DCOSS-IoT 2025, Tuscany, Italy, 9-11 June 2025. [Link] [PDF]