Using the Mosquitto implementation in an embedded environment

Sammanfattning: An essential challenge of the Internet of Things is how to share data between embedded systems. One way of doing this is with the protocol MQTT. MQTT is a message distribution protocol which uses a publish and subscribe method to share data. The company Fältcom uses an implementation of MQTT called Mosquitto to distribute data between their units. Fältcom has developed an embedded unit called MIIPS C which uses the Mosquitto implementation to function as a message broker. The broker is the center of communication and all other units send their messages through the broker. The questions of this thesis regards how well Mosquitto works in an embedded environment with hardware limitations and an unstable internet connection. To answer these questions tests were run on a MIPPS while observing key metrics such as CPU usage and latency. The results are summarized to compare performance between different cases. The results show how Mosquitto works well in an embedded environment if configured correctly. The configuration has to limit message size and how many messages the broker can store, in order to ensure that the broker does not run out of memory.