  We use runtime verification (RV) to check various specifications in a smart
apartment. The specifications can be broken down into three types: behavioral
correctness of the apartment sensors, detection of specific user activities
(known as activities of daily living), and composition of specifications of the
previous types. The context of the smart apartment provides us with a complex
system with a large number of components with two different hierarchies to
group specifications and sensors: geographically within the same room, floor or
globally in the apartment, and logically following the different types of
specifications. We leverage a recent approach to decentralized RV of
decentralized specifications, where monitors have their own specifications and
communicate together to verify more general specifications. We leverage the
hierarchies, modularity and re-use afforded by decentralized specifications to:
(1) scale beyond existing centralized RV techniques, and (2) greatly reduce
computation and communication costs.
