Page 170 - 5G Basics - Core Network Aspects

1 Core network aspects

1 Scope
This Recommendation defines the functional architecture of software-defined networking (SDN) by
describing a layered architecture, the functional components of the architecture and its reference points.
Details of multi-layer management are provided in Annex A and the role of orchestration is addressed in
Appendix I. The architecture is based on [ITU-T Y.3300] which defines the SDN framework and [ITU-T Y.3301]
which describes the functional requirements of the SDN architecture which the present Recommendation
has to fulfil.

2 References
The following ITU-T Recommendations and other references contain provisions which, through reference in
this text, constitute provisions of this Recommendation. At the time of publication, the editions indicated
were valid. All Recommendations and other references are subject to revision; users of this Recommendation
are therefore encouraged to investigate the possibility of applying the most recent edition of the
Recommendations and other references listed below. A list of the currently valid ITU-T Recommendations is
regularly published. The reference to a document within this Recommendation does not give it, as a stand-
alone document, the status of a Recommendation.

[ITU-T M.3400] Recommendation ITU-T M.3400 (2000), TMN management functions.
[ITU-T Y.3001] Recommendation ITU-T Y.3001 (2011), Future networks: Objectives and design goals.

[ITU-T Y.3300] Recommendation ITU-T Y.3300 (2014), Framework of software-defined networking.
[ITU-T Y.3301] Recommendation ITU-T Y.3301 (2016), Functional requirements of software-defined
networking.
[ITU-T Y.3320] Recommendation ITU-T Y.3320 (2014), Requirements for applying formal methods to
software-defined networking.

3 Definitions

3.1 Terms defined elsewhere
This Recommendation uses the following terms defined elsewhere:

3.1.1 functional component [b-ITU-T Y.3502]: A functional building block needed to engage in an activity,
backed by an implementation.

3.1.2 network virtualization [b-ITU-T Y.3011]: A technology that enables the creation of logically isolated
network partitions over shared physical networks so that heterogeneous collection of multiple virtual
networks can simultaneously coexist over the shared networks. This includes the aggregation of multiple
resources in a provider and appearing as a single resource.
3.1.3 software-defined networking [ITU-T Y.3300]: A set of techniques that enables to directly program,
orchestrate, control and manage network resources, which facilitates the design, delivery and operation of
network services in a dynamic and scalable manner.

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