Similarly to elsewhere on the Internet, practical security in the Internet of Things (IoT) is achieved by combining an array of mechanisms, at work at all layers of the protocol stack, in system software, and in hardware. Standard protocols such as Datagram Transport Layer Security (DTLS 1.2) and Transport Layer Security (TLS 1.2) are often recommended to secure communications to/from IoT devices. Recently, the TLS 1.3 standard was released and DTLS 1.3 is in the final stages of standardization. In this paper, we give an overview of version 1.3 of these protocols, and we provide the first experimental comparative performance analysis of different implementations and various configurations of these protocols, on real IoT devices based on low-power microcontrollers. We show how different implementations lead to different compromises. We measure and compare bytes-over-the-air, memory footprint, and energy consumption. We show that, when DTLS/TLS 1.3 requires more resources than DTLS/TLS 1.2, this additional overhead is quite reasonable. We also observe that, in some configurations, DTLS/TLS 1.3 actually decreases overhead and resource consumption. All in all, our study indicates that there is still room to optimize the existing implementations of these protocols.

翻译：与互联网上其他地方类似,互联网上物品(IoT)的实际安全是通过在协议堆、系统软件和硬件的各个层面工作的各种机制的结合实现的。标准协议,如数据传输层安全(DTLS 1.2)和运输层安全(TLS 1.2),常常被推荐确保与IoT装置的通信。最近,TLS 1.3标准已经发布,DTLS 1.3标准正处于标准化的最后阶段。在本文件中,我们对这些协议的1.3版作了概述,并且根据低功率微控制器,对这些协议的不同执行和各种配置,对实际的IoT装置,提供了第一次试验性的比较性能分析。我们展示了不同的执行方式如何导致不同的妥协。我们测量和比较了空上、记忆足迹和能源消耗的字节点。我们表明,当DLS/TLS 1.3需要比DLS/TLS 1.2的更多资源时,这种额外的间接费用是相当合理的。我们还注意到,在某些配置中,DLS/TLS 1.3 3 实际减少间接费用和资源消耗。所有研究都表明,现有协议是最佳的。