Page 276 - Shaping smarter and more sustainable cities - Striving for sustainable development goals

Figure 41 – Pictorial representation of the aim of IoT‐A
As in any metaphoric representation, this tree does not claim to be fully consistent in its depiction,
hence, it should therefore not be taken too strictly. On the one hand, the roots of this tree are
spanning across a selected set of communication protocols (6lowpan, ZigBee, IPv6,…) and device
technologies (sensors, actuators, tags,..) while on the other hand, the flowers/leaves of the tree
represents the whole set of IoT applications that can be built from the sap (information/knowledge)
coming from the roots. The trunk of the tree is of the utmost importance here, beyond the fact it
represents the IoT‐A project. This trunk represent the Architectural Reference Model (which means
here Reference Model + Reference Architecture a.k.a. ARM), the set of models, guidelines, best
practices, views and perspectives that can be used for building fully interoperable IoT Concrete
architecture (and therefore systems). Using this tree, one aims at selecting a minimal set of
interoperable technologies (the roots) and proposing the potentially necessarily set of enablers or
building blocks, etc. (the trunk) that enable the creation of a maximal set of interoperable IoT
systems (the leaves).

Reference model and reference architecture:

The IoT reference model provides the highest abstraction level for the definition of the IoT‐A
architectural reference model. It promotes a common understanding of the IoT domain. The
description of the reference model includes a general discourse on the IoT domain, a domain model
as a top‐level description, an information model explaining how IoT knowledge is going to be
modelled, and a communication model in order to understand interaction schemes for smart
objects. The definition of the IoT reference model is conforming to the OASIS reference model
definition [Mackenzie, 2006]. A more detailed description of the IoT reference model is provided in
http://www.iot‐a.eu/arm.

266 ITU‐T's Technical Reports and Specifications