Security and Performance Analysis of MQTT Protocol with TLS in IoT Networks

Internet of Things (IoT) is a sophisticated concept of the traditional internet. In IoT, all things in our lives can be connected with the internet or with each other to exchange data and perform specific functions through the network. However, combining several devices-especially by unskilled users-may pose a number of security risks. In addition, some commonly used communication protocols in the IoT area are not secure. Security, on the other hand, increases overhead by definition, resulting in performance degradation. The Message Queuing Telemetry Transport (MQTT) protocol is a lightweight protocol and can be considered as one of the most popular IoT protocols, it is a publish/subscribe messaging transport protocol that uses a client-server architecture. MQTT is built to run over TCP protocol, thus it does not provide any level of security by default. Therefore, Transport Layer Security (TLS) can be used to ensure the security of the MQTT protocol. This paper analyzed the impact on the performance and security of the MQTT protocol in two cases. The first case, when using TLS protocol to support the security of the MQTT protocol. The second case, using the traditional MQTT without providing any level of security for the exchanged data. The results indicated that there is a tradeoff between the performance and the security when using MQTT protocol with and without the presence of TLS protocol.