Page 719 - 2015 Security in Telecommunications and Information Technology

Unleashing the potential of the Internet of Things 5

Appendix I

Deployment model with WoT
(This appendix does not form an integral part of this Recommendation.)

In [b-ITU-T Y.2063] the physical device on the WoT is divided into two categories: constrained
device and fully-fledged device.
• constrained device: A constrained device cannot connect to the Internet and has no
functionality of the web. The device interacts with an agent of the WoT broker.
• fully-fledged device: A fully-fledged device has the functionalities of the web. The device
can interact, not only with the WoT broker, but also with the services on the web.

The constrained device and the fully-fledged device do not have the device object and hence they
correspond to the non-basic device described in this Recommendation. The constrained device
communicates with the HGW through the adapter then further communicates with the management
PF. The fully-fledged device can also communicate with the management PF by way of the HGW.
In this Recommendation, the HGW, which has the function of the resource information collector,
manages all of the devices connected to it through the HN including constrained devices and
fully-fledged devices.

[b-ITU-T Y.2063] defines the WoT broker and the physical devices can be accessed as web resources
through it from the application. Its functional architecture is divided into the service layer and the
adaptation layer where the service layer corresponds to the management PF and the adaptation layer
corresponds to the HGW in this Recommendation.
The web adaption function of the WoT broker supports only the adaptation of the communications
protocol to the web protocol for communication between the physical devices and the WoT services.
Therefore the web broker supports the P-D reference point only in this Recommendation. Figure I.1 shows
the deployment model in which the HGW is connected to a constrained device and a fully-fledged device.

Figure I.1 – Deployment model with WoT
The management PF provides the virtual devices to the application developers to be treated as web
resources through the web-based application interface so that they can develop applications for the
mash-up service defined in [b-ITU-T Y.2063], which is a combined service integrating WoT services
in a WoT broker with web services outside of the WoT broker.

In this way the architecture in this Recommendation provides the HEMS and the other HN services
with the WoT.

Rec. ITU-T Y.4409/Y.2070 (01/2015) 705