Towards a comfortable, energy-efficient office using a publish-subscribe pattern in an internet of things environment

Abstract

The modern office is maintained by air conditioners, heaters, lights, smoke detectors, thermostats and other devices. Manufacturers are continually improving these various devices and adding more features –especially Internet connectivity. These new devices are often called smartdevices. The Internet of Things is the new paradigm of more and more physical objects being connected to the Internet. As these objects begin interacting, mechanisms need to be in place to route data messages from the many objects to the correct applications which process that data. For example, the data from the thermostat in Office A must not be routed to the application controlling the temperature in Office B. One such mechanism is the publish-subscribe pattern often just called the pub-sub pattern. The pub-sub pattern enables applications to subscribe to data from certain resources. When a resource publishes data, the surrounding platform ensures that the data is forwarded to the correct subscribers. This paper describes an implementation of the pub-sub pattern specifically for an Internet of Things platform which operated at four levels –sensors (and actuator), Supervisors, Middleware, and application. This platform was specifically instantiated to control a typical office meeting room. The instantiation monitors the state of the doors and windows (open or closed), whether there are people in the room, the current temperature in the room, and the current electrical consumption. It then makes intelligent decisions as to how best to control the air conditioner in the meeting room.