Page 93 - 5G Basics - Core Network Aspects

Core network aspects 1

1 Scope
This Recommendation defines network virtualization and provides an overview of, and motivation for,
network virtualization. It also describes problem spaces, design goals, and applicability of network
virtualization.

Use cases for network virtualization are discussed in an appendix.

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 Y.3001] Recommendation ITU-T Y.3001 (2011), Future networks: Objectives and design goals.

3 Definitions

3.1 Term defined elsewhere
This Recommendation uses the following term defined elsewhere:
3.1.1 future network (FN) [ITU-T Y.3001]: A network able to provide services, capabilities, and facilities
difficult to provide using existing network technologies.

3.2 Terms defined in this Recommendation

This Recommendation defines the following terms:
3.2.1 logical resource: An independently manageable partition of a physical resource, which inherits the
same characteristics as the physical resource and whose capability is bound to the capability of the physical
resource.
NOTE – "independently" means mutual exclusiveness among multiple partitions at the same level.
3.2.2 logically isolated network partition (LINP): A network that is composed of multiple virtual resources
which is isolated from other LINPs.
NOTE – "logically isolated", which is the counter concept of "physically isolated", means mutual exclusiveness of the
subjects (i.e., network partition, in this case), while the original subjects may be physically united/shared within the
common physical constraints.
3.2.3 virtual resource: An abstraction of physical or logical resource, which may have different
characteristics from the physical or logical resource and whose capability may be not bound to the capability
of the physical or logical resource.

NOTE – "different characteristics" means simplification or extension of the resource characteristics. "different
characteristics" allows the virtual resource to expose access or control methods different from the original physical or
logical resource.
3.2.4 network virtualization: A technology that enables the creation of logically isolated network
partitions over shared physical networks so that heterogeneous collections 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.
NOTE – Refer to the note of the definition of LINP for "logically isolated".

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