Energy consumption evaluation of Post-Quantum TLS 1.3 for resource-constrained embedded devices

Post-Quantum cryptography (PQC), in the past few years, constitutes the main driving force of the quantum resistance transition for security primitives, protocols and tools. TLS is one of the widely used security protocols that needs to be made quantum safe. However, PQC algorithms integration into TLS introduce various implementation overheads compared to traditional TLS that in battery powered embedded devices with constrained resources, cannot be overlooked. While there exist several works, evaluating the PQ TLS execution time overhead in embedded systems there are only a few that explore the PQ TLS energy consumption cost. In this paper, a thorough power/energy consumption evaluation and analysis of PQ TLS 1.3 on embedded systems has been made. A WolfSSL PQ TLS 1.3 custom implementation is used that integrates all the NIST PQC algorithms selected for standardisation as well as 2 out of 3 of those evaluated in NIST Round 4. Also 1 out of 2 of the BSI recommendations have been included. The PQ TLS 1.3 with the various PQC algorithms is deployed in a STM Nucleo evaluation board under a mutual and a unilateral client-server authentication scenario. The power and energy consumption collected results are analyzed in detail. The performed comparisons and overall analysis provide very interesting results indicating that the choice of the PQC algorithms in TLS 1.3 to be deployed on an embedded system may be very different depending on the device use as an authenticated or not authenticated, client or server. Also, the results indicate that in some cases, PQ TLS 1.3 implementations can be equally or more energy consumption efficient compared to traditional TLS 1.3.