Page 530 - Unleashing the potenti al of the Internet of Things

5 Unleashing the potential of the Internet of Things

3.1.5 sensed data [ITU-T F.744]: Data sensed by a sensor that is attached to a specific sensor
node.
NOTE – The sensed data are collected from USN resources via USN middleware and stored in a sensed data
repository.
3.1.6 ubiquitous sensor network (USN) [ITU-T Y.2221]: A conceptual network built over
existing physical networks which makes use of sensed data and provides knowledge services to
anyone, anywhere and at anytime, and where the information is generated by using context
awareness.

3.1.7 USN middleware [ITU-T Y.2221]: A set of logical functions to support USN applications
and services.

3.2 Terms defined in this Recommendation
This Recommendation defines the following terms:
3.2.1 metadata: Description of USN resources which include types of operations supported,
attributes for those operations, etc.

3.2.2 open USN service: USN service which provides unified access to USN resources and
sensed data/semantic data through heterogeneous USN middleware.

3.2.3 semantic data: Data translated into resource description framework (RDF) [b-RDF] form
from metadata of USN resources and sensed data, and data processed by the Semantic inference
functional entity (FE) from data represented in RDF form. These data are stored in a Semantic data
repository.
3.2.4 USN resource: An entity that provides a USN service including sensor, actuator, sensor
node, sensor network and gateway.

4 Abbreviations and acronyms

This Recommendation uses the following abbreviations and acronyms:
API Application Programming Interface

FE Functional Entity
LOD Linked Open Data

RDF Resource Description Framework
REST Representational State Transfer

SPARQL SPARQL Protocol and RDF Query Language
URI Uniform Resource Identifier
USN Ubiquitous Sensor Network

5 Conventions

None.

6 Open USN service description and characteristics

USN services require USN applications to have knowledge of USN middleware and sensors or
sensor networks in order to access USN resources. For example, heterogeneous USN middleware is
not easily accessed by applications since each USN middleware may have proprietary application
programming interfaces (APIs) which may hinder access to various USN resources attached to the
USN middleware.

516 Rec. ITU-T Y.4402/F.747.4 (12/2013)