Internet of Things Architecture

Internet of Things – Architecture © - 83 -

3.6 Communication Model

The IoT Communication Model aims at defining the main communication
paradigms for connecting elements, as defined in the IoT Domain Model. We
provide a reference set of communication rules to build interoperable stacks,
together with insights about the main interactions among the elements of the
IoT Domain Model. We propose a Communication Model that leverages on the
ISO OSI 7-layer model for networks and aims at highlighting those peculiar
aspects inherent to the interoperation among different stacks, which we will call
in what follows, interoperability features. Further, the application of
communication schemes, such as application layer gateways, transparent
proxy, network virtualization, etc, to different IoT network types is discussed.

In particular, with reference to our ―Read Thread‖ example of Section 2.3, the
IoT Communication Model can be used to model how the monitoring Sensors of
the truck can seamlessly interact with Ted‘s phone and how it can communicate
with the store enterprise system.

The IoT Communication Model has multiple usages. For instance, it can guide
the definition of the Communication Functional Components from which the
Communication Functional Group is composed of. Finally, it can be used to
derive the Communication best practices, as depicted in the following pictures:

Figure 16 : IoT Communication Model usages

In this figure above: (left) using the CM together with the Unified Requirements
UNIs) to define the Communication FG; (right) deriving Communicaton Best
Practices thanks to the CM and UNIs.

3.6.1 IoT Domain Model element communications

For the IoT Communication Model, it is important to identify the communication-
system elements and/or the communicating Users among those defined in the
IoT Domain Model. One, if not the main peculiarity of the IoT is that Users can
belong to many disjoint categories: Human Users, Services or Active Digital
Artefacts. While the same picture is emerging in today‘s Internet usage, the
percentage of human-invoked communication will be even lower in the IoT.
Moreover, entities can be physical, digital, or virtual. While a Physical Entity
cannot directly take part to communication, it can exploit Services associated to
its virtual counterpart.

The communication between these users needs to support different paradigms:
unicast is the mandatory solution for one-to-one connectivity. However,