A Practical Attestation Protocol for Autonomous Embedded Systems presented at IEEEEuroS&P 2019

by Stefan Katzenbeisser, Florian Kohnhäuser, Niklas Büscher,

Summary : With the recent advent of the Internet of Things (IoT), embedded devices increasingly operate collaboratively in autonomous networks. A key technique to guard the secure and safe operation of connected embedded devices is remote attestation. It allows a third party, the verifier, to ensure the integrity of a remote devices, the prover. Unfortunately, existing attestation protocols are impractical when applied in autonomous networks of embedded systems due to their limited scalability, performance, robustness, and security guarantees. In this work, we propose a novel attestation protocol that is particularly suited for autonomous embedded systems. Our protocol is the first that (i) enables many low-end prover devices to attest their integrity towards many potentially untrustworthy low-end verifier devices, (ii) is fully decentralized, thus, able to withstand network disruptions and arbitrary device outages, and (iii) is in addition to software attacks capable of detecting physical attacks in a much more robust way than any existing protocol. We implemented our protocol, conducted measurements, and simulated large networks. The results show that our protocol is practical on low-end embedded devices, scales to large networks with millions of devices, and improves robustness by multiple orders of magnitudes compared with the best existing protocols.