Specifying an MQTT Tree for a Connected Smart Home Adrien van den Bossche 1(B) , Nicolas Gonzalez 1 , Thierry Val 1 , Damien Brulin 2 , Fr´ed´eric Vella 1 , Nadine Vigouroux 1 , and Eric Campo 2 1 IRIT, CNRS, UPS, UT1, UT2J, Universit´e de Toulouse, Toulouse, France {Adrien.van-den-Bossche,Nicolas.Gonzalez,Thierry.Val,Frederic.Vella, Nadine.Vigouroux}@irit.fr 2 LAAS-CNRS, Universit´e de Toulouse, CNRS, UT2J, Toulouse, France {Damien.Brulin,Eric.Campo}@laas.fr Abstract. Ambient Assisted Living (AAL) represents one of the most promising Internet of Things applications due to its inﬂuence on the quality of life and health of the elderly people. However, the interoper- ability is one of the major issues that needs to be addressed to promote the adoption of AAL solutions in real environments, and to ﬁnd a way of common exchange between the available connected tools to share the data exchanged. This article will present software buses needs and spec- ify an API based on a MQTT software bus treelike architecture. An example is given to illustrate the eﬃciency of the API developed in a smart home. Keywords: Ambiant assisted living · Software bus · MQTT Connected devices · Elderly people · Smart home 1 Introduction Ambient Assisted Living (AAL) represents one of the most promising Internet of Things (IoT) applications due to its inﬂuence on the quality of life and health of the elderly people [1]. AAL can be used for preventing, curing, and improving wellness and health conditions of older adults [2]. IoT consists of connected smart objects capable of identifying, locating, sensing and assisting. [3] gives a survey on the emergence of AAL tools for older adults based on an ambient intelligence paradigm. The technologies mentioned include smart homes (ambient sensors), wearable and mobile sensors, mobile devices, assistive devices, automated sys- tems of processing, and so on, which require a common exchange protocol to share their real time data [4]. However, the interoperability is one of the major issues to be addressed to promote the adoption of AAL solutions in real envi- ronments. In the context of the connected smart homes, the software buses establish a simple and eﬀective way to transfer these data. Due to their open nature, the software buses facilitate this information sharing and allow real time exchanges. c  Springer International Publishing AG, part of Springer Nature 2018 M. Mokhtari et al. (Eds.): ICOST 2018, LNCS 10898, pp. 236–246, 2018. https://doi.org/10.1007/978-3-319-94523-1_21