NS-3 Based Open-Source Implementation of MQTT Protocol for Smart Building IoT Applications

Emerging concept of smart buildings requires machine-to-machine communication based on low overhead between interconnected Internet-of-Thing (IoT) nodes. Message Queuing Telemetry Transport (MQTT) is a subscriber / publisher based modern data transfer protocol that is open-source, lightweight, and well suited for IoT applications. This paper presents details of an MQTT protocol implementation incorporated in a well-known network simulator, NS-3, to model different IoT scenarios in smart buildings. Several configurations have been inquired and included in the paper to demonstrate the efficacy of the NS-3 models and depict the ease with which the behavior of different IoT applications can be modelled and evaluated before actual deployment. The performance of MQTT packet transmission and its sequence between the publisher nodes and different subscriber nodes has been analyzed and presented in the paper through several case studies.