Performance Evaluation of Post-Quantum TLS 1.3 on Resource-Constrained Embedded Systems.

Transport Layer Security (TLS) constitutes one of the most widely used protocols for securing Internet communications and has also found broad acceptance in the Internet of Things (IoT) domain. As we progress toward a security environment resistant to quantum computer attacks, TLS needs to be transformed to support post-quantum cryptography. However, post-quantum TLS is still not standardised, and its overall performance, especially in resource-constrained, IoT-capable, embedded devices, is not well understood. In this paper, we showcase how TLS 1.3 can be transformed into quantum-safe by modifying the TLS 1.3 architecture in order to accommodate the latest Post-Quantum Cryptography (PQC) algorithms from NIST PQC process. Furthermore, we evaluate the execution time, memory, and bandwidth requirements of this proposed post-quantum variant of TLS 1.3 (PQ TLS 1.3). This is facilitated by integrating the pqm4 and PQClean library implementations of almost all PQC algorithms selected for standardisation by the NIST PQC process, as well as the alternatives to be evaluated in a new round (Round 4). The proposed solution and evaluation focuses on the lower end of resource-constrained embedded devices. Thus, the evaluation is performed on the ARM Cortex-M4 embedded platform NUCLEO-F439ZI that provides 180 MHz clock rate, 2 MB Flash Memory, and 256 KB SRAM. To the authors' knowledge, this is the first systematic, thorough, and complete timing, memory usage, and network traffic evaluation of PQ TLS 1.3 for all the NIST PQC process selections and upcoming candidate algorithms, that explicitly targets resource-constrained embedded systems.