Towards interoperable and sustainable smart homes

In an idealized vision of a fully integrated smart home, all the operations of a house can be efficiently controlled by a unified smart ubiquitous application. However, we are far from realizing this scenario. A main barrier is the proliferation of incompatible standards and protocols used by various device manufacturers, which makes the smooth integration of appliances from different vendors a very complex process. Having a heterogeneous ecosystem of devices implies that even the development of simple applications requires advanced programming skills and a considerable amount of time. Lately, the Internet is starting to penetrate in embedded computing, with IPv6 expected to merge the physical and the digital world. The potential of the Internet of Things (IoT) is widely discussed, and slowly being realized in pilot studies and beyond. It was a natural extension that the Web of Things (WoT) is proposed for interconnecting the expanding ecosystem of Internet-enabled embedded devices, by reusing well-accepted and understood Web principles. Thus, in this paper we motivate the WoT, present an architecture for the application of WoT in smart homes and demonstrate through case studies. that energy-aware smart homes have the potential to provide flexible solutions to challenges such as energy awareness, energy conservation and the integration of future smart homes to the smart grid of electricity. By combining sensor devices with residential smart power outlets, the foundational pillars are built towards truly Web-based energyaware smart homes. Issues such as interoperability of heterogeneous home devices by employing Web techniques, home automation by means of energy-saving rules, energy awareness by means of real-time feedback and local/social comparisons, and the integration of smart homes to the smart grid of electricity are discussed.