A Practical Attestation Protocol for Autonomous Embedded Systems

Abstract

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 device, 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 PASTA, a novel attestation protocol that is particularly suited for autonomous embedded systems. PASTA 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 PASTA is practical on low-end embedded devices, scales to large networks with millions of devices, and improves robustness by multiple orders of magnitude compared with the best existing protocols.

RESCUE: A Resilient and Secure Device-to-Device Communication Framework for Emergencies

“…Additionally, remote attestation will become increasingly widespread with upcoming technologies [27], [28] and MAs could act as verifiers and thus identify new users during a crisis. Usually, a backbone in the form of stable connections, e. g., [29], [30], [31]. In practice, though, remote attestation without backbone access has not yet been implemented.…”

A Survey on Recent Advanced Research of CPS Security

“…PASTA [132] is a new attestation protocol for autonomous embedded systems, especially low-end embedded devices. It is fully decentralized, as each prover initiates a new token generation periodically to ensure freshness, which makes network disruptions or arbitrary device outages tolerable.…”

Fadia

“…Nonetheless, this protocol is not applicable for large networks. Recently, Kohnhauser et al proposed PASTA [27], an autonomous RA protocol in which provers create multiple spanning trees in the network and generate the so-called tokens to attest the provers participating in the tree. Each token embeds the proofs of all the nodes in the tree.…”

“…Remote attestation (RA) helps achieve this goal by enabling a device acting as a prover to prove the integrity of its software configuration to a remote verifier. There exist many RA solutions in the literature [2,[25][26][27]. While existing solutions have improved a lot in terms of scalability, security and robustness, they unfortunately fall short in addressing the heterogeneous aspects of the network.…”

“…We show by experiments that fairness can provide a better performance for a RA protocol; • We present FADIA a RA protocol that supports efficient addition of devices at runtime, without extra overhead, but only with a limited sacrifice of the connectivity of the devices; • We implement our solution on heterogeneous embedded systems, namely Rasberry Pi 2 devices and Tmote Sky sensor nodes; • We evaluate the performance of our solution in heterogeneous and homogeneous networks. We compare the results of our solution to the other best existing protocols [26,27] in the same network scenarios. The results show that our solution outperforms the previous solutions in all aspects.…”