Improving MQTT Data Delivery in Mobile Scenarios:Results from a Realistic Testbed

© 2016 Jorge E. Luzuriaga et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
MQTT is being widely used for data delivery in IoT applications but its architecture does not properly handle mobility when disconnection periods tend to be large. In this paper we describe an experimental evaluation, made in a real environment, of a solution that guarantees that there is no information loss when variable length hand-offs appear due to the movement of a node. Our proposal modifies the classical publish/subscribe scheme by introducing an intermediate buffer that takes care of message transfer. Finally, we study the impact related to the connectivity of mobile devices of the use of the standard Linux Network Manager. We propose a cross-layer solution that improves the device connectivity in conjunction with the data layer management. We show that our solution improves the data delivery guaranteeing that no information is lost.