The Things in the Internet of Things
HALLER S., The Things in the Internet of Things, Internet of Things Conference 2010, Tokyo, Japan (http://www.iot2010.org/), 2010
|Abstract||The Internet of Things is a hyped term and many definitions for it exist. Worse still, it comes with a lot of related terminology that is not used uniformly either, hindering scientific discourse. This paper tries to bring clarity by describing the most important terms like things, devices, entities of interest, resources, addressing, identity and, more importantly, the relationships between them.|
- Kevin ASHTON: an informational network that allows the look-up of information about real-world objects by means of a unique ID called Electronic Product Code (EPC) and a resolution mechanism (ONS)
- more recent definition: a network of sensors, actuators and autonomous objects interacting with each other directly; N.B. "All the different definitions of the term "Internet of Things" have in common that it is related to the integration of the physical world with the virtual world of the Internet."
Entity of interest: In an IoT world, there are "physical objects one wants to be able to track, to monitor and to interact with". "These are the things of the Internet of Things, or to use a clearer term, the entities of interest." "Basically any object - including the attributes that describe it and its state - that is relevant from a user or application perspective can be regarded as an entity of interest."
(Technical Communication) Devices:
- used to monitor and interact with one or more entities of interest and make the connection to the Internet
- they can be attached or embedded in the entities themselves (attached/embedded devices), thus creating smart things, or they can be installed in the environment of things to be monitored (environmental devices)
- examples of devices: RFID readers, sensors and actuators,embedded computers (i.e. microcontrollers), mobile phones...
- devices may be also entities of interest when we can look at them from a technical or management perspective
- in my opinion, we can also have other devices, remote devices, that may acquire resources from the embedded, environmental and attached devices
- they are hosted by devices
- they are computational elements that provide the technical link to the entities of interest (e.g., they offer information about the thing, like an identifier or sensed data, and they may provide actuation capabilities as well)
- access to resources from the outside world finally happens through services
- resources may offer a service interface directly, or services inside the network act as proxies for the actual resources, possibly providing additional levels of aggregation and abstraction (N.B. There is an other element: interfaces to access services!! Interfaces are devices which are not necessarily embedded, attached or environmental (for example, they may allow us to remotely access resources and use services), and they allow us to access services).
Relationship between all these elements: "An entity of interest is monitored by a device in the environment, or it can also have a device attached to or embedded in it. As described above both classes of devices can be seen as entities of interest when looking from a management perspective, hence the subclass relationship. The device hosts one or more resources which are accessed through services."
Examples of differences between entities of interest and devices.
Differences between identity and identifiers: every entity of interest has one identity, but perhaps more than one identifier: for example, a unique ID for the entity of interest and an address (IP) for the device embedded. To find information about a specific ID we can use resolution (EPCIS) or discovery (like googling).
See also Overview of the Internet of Things — Recommendation for the definitions of device and thing.