IoT interoperability is critical to the realization of the IoT on a global scale. This paper examines how seemingly obvious choices for perfect IoT interoperability are not so perfectly rational and offers the concept of "Rational Interoperability" as a means to frame and to scope the discussion. We identify why a new framing conceptualization adds value. We explore the gradations, progression and implications of Rational Interoperability: from good-enough interoperability in a pervasively connected world, to enriched interoperability for trusted groups of Things, to the aspirational goal to use interoperability requirements to guide the behavior of groups of Things toward the common good. To motivate Rational Interoperability, we describe architectural shifts underway in the IoT and present key building blocks, both of which play pivotal roles and impact its realization. We examine pragmatic near-term goals for IoT interoperability, as well as longer-term research directions. Throughout, we share lessons learned from IoT standards, highlighting pragmatic and philosophical viewpoints. Finally, we identify the gaps, challenges and opportunities in realizing IoT interoperability, including meta-data handling, enhanced discovery, data-driven insights, data-centric networks and the coordination of collective behaviors.

The emergence of Information Technology (IT) based sensing has received increasing attention and acceptance in buildings due to its noninvasive nature and its ability in delivering real-time and potentially highly personalized feedback to building energy and comfort management. This study presents results of a pilot deployment experiment on such an IT-based sensing system - Personal Office Energy Monitor (POEM) developed by Intel Labs. The pilot study shows that with appropriate analytic methods the POEM sensor data could be transferred into valuable inputs to building management system (BMS). This study applies building science principle based models as the first step to calculate intermediate building performance indices based on raw measurement data. The intermediate performance indices are then further analyzed in order to reveal potential means to improve a building's operational energy efficiency and occupant comfort. Results demonstrate that POEM sensor data could lead to energy saving opportunities through localized comfort management, plug load sensing and scheduling, and occupancy based building control. As an IT platform-integrated and occupant centered sensing system, POEM provides a convenient, low-cost, and efficient sensing solution to the next generation of smart buildings, featured by its ability in assisting BMS to improve operational building energy efficiency without compromising occupants' thermal comfort and indoor environmental quality.