The platform is based on an IoT service/resource model
that has been developed by the European project BUTLER [2].
In this model each IoT device is exposed as a service to access
resources provided by devices (mainly data and actions). From
a functional point of view, a resource is characterized by the
following elements: an identifier, a resource type (Sensor data,
Action, State variable, Property), a set of attributes and a set of
access methods (see Figure 3).