future internet Article Improvements of the xAAL Home Automation System Christophe Lohr * and Jérôme Kerdreux IMT Atlantique, Lab-STICC, UMR CNRS 6285, F-29238 Brest, France;
[email protected] * Correspondence:
[email protected]; Tel.: +33-(0)2-29-00-14-05 Received: 30 April 2020; Accepted: 10 June 2020; Published: 12 June 2020 Abstract: The xAAL home automation system has been designed on the basis of distributed systems principles with messages passing and home network communications over IP. The proposal makes extensive use of standards and provides a clear separation of roles along the distributed system with no predominant actor. This allows openness and interoperability. This objective can be reached once all parts are convinced: consumers, manufacturers, service providers, etc. To get a broad adoption, the proposal comes with fine-tuned communication, architecture, security, and simplicity. Tests and experiments in the long term have led us to optimize the protocol, adjust the architecture, and rearrange device descriptions. This paper provides a full description of the improved system, with all details to make feasible compatible alternative implementations. It also discusses alternatives and all aspects that led us to make structuring choices: CBOR messages on an IP multicast channel, intranet communication, ciphering with Poly1305/Chacha20, structured and extensible abstract device description, and a distributed system architecture. Keywords: home automation; internet of things; interoperability; comfort and wellbeing; ambient assisted living 1. Introduction Ambient Assisted Living (AAL) technologies aim to use digital products and services to ensure that dependents and seniors at home stay safe, healthy, active and independent. It includes smart devices, communication networks and software applications.