A comprehensive and realistic performance evaluation of post-quantum security for consumer IoT devices

The computational capacity envisaged for quantum computers poses a significant threat to today's traditional cryptographic algorithms. Although they are not yet large enough to compromise current cryptographic protocols, one can practice retrospective decryption since data packets traveling through the Internet can be easily sniffed. This threat extends to wireless communication security within consumer IoT devices that use lightweight cryptography due to limited computational power. Thus, countermeasures against potential quantum attacks should be preemptively adopted. NIST is leading efforts to standardize several algorithms as quantum-resistant Key Exchange Mechanisms (KEMs) and Digital Signatures. In this paper, we investigate the viability of these Post-Quantum algorithms in the Transport Layer Security (TLS) of power-constrained IoT devices. Specifically, it focuses on two widely used IoT network protocol stacks, i.e., Bluetooth Low Energy (BLE) and Wi-Fi. To this end, we build a realistic IoT testbed running IP over BLE. Our evaluation considers the impact of several realistic factors for the first time, such as using a chain of certificates on the server side and incorporating certificate validation methods such as Online Certificate Status Protocol (OCSP) and Certificate Revocation Lists (CRL). We also evaluate the impact of mutual authentication between the server and the client. Utilizing the outcomes of this evaluation, we then propose a novel approach for IoT devices to dynamically choose the most efficient KEM algorithm for TLS based on the device's physical network interface. The performance results provide valuable insights with respect to the TLS latency and energy consumption of consumer IoT devices.