Internet of Things Architecture

Internet of Things – Architecture © - 55 -

Sensor Node :

Device

lookupAssociations :

Service

resolveService :

Service

Measurement

Service : Service

AndroidApp :

Active Digital

Artefact

Temperature

Sensor :

Sensor

Humidity Sensor :

Sensor

Alarm :

On-Device

Resource

Load Carrier :

Physical Entity

is attached to

monitors monitors

is attached to

hosts

exposes

subscribes invokes

invokes

Figure 5 : Instantiated IoT Domain Model for the ―Red Thread‖ example (see Section

2.3).

Figure 5 shows an instance diagram of central aspects of the use-case scene
in Section 2.3. This example was cast in the language of the IoT Domain Model
and then illustrated by use of UML. Information about UML can be found
elsewhere in the literature [Fowler 2003] or by searching for terms such as
―UML tutorial‖ on the web.

As we can see in Figure 5 , the important entities that are relevant for our use
case are depicted with blocks of different colours. For instance, there is our
truck driver ―Ted‖ represented by as a yellow box (viz. instance), and the
temperature sensor (that triggers an alarm after ―Ted‖ had turned off the engine
of the truck) is represented as a blue instance. Already at this stage we can
easily deduct that there is some colour coding involved that reflects an aspect of
the respective entity. What these colours exactly stand for is discussed in detail
in the next sections. There is also a categorisation in textual form, as the entity
name that we know from our recurring example is succeeded by an entity
category such as Sensor in the case of the humidity or temperature sensors