Page 397 - 5G Basics - Core Network Aspects

Core network aspects 1

1 Scope
This Recommendation describes the capabilities of multi-connection to support the enhanced multimedia
telephony service (eMMTel).

The scope of this Recommendation includes scenarios, service features, requirements, functional
architecture, information flows and other aspects such as security and charging for eMMTel services over
the multi-connection functional architecture.
It is noted that eMMTel service in this Recommendation applies the IMS-based NGN environment.

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 Q.1706] Recommendation ITU-T Q.1706/Y.2801 (2006), Mobility management requirements
for NGN.
[ITU-T X.200] Recommendation ITU-T X.200 (1994) | ISO/IEC 7498-1:1994, Information technology –
Open Systems Interconnection – Basic Reference Model: The basic model.

[ITU-T X.800] Recommendation ITU-T X.800 (1991), Security architecture for Open Systems
Interconnection for CCITT applications.

[ITU-T Y.2001] Recommendation ITU-T Y.2001 (2004), General overview of NGN.
[ITU-T Y.2027] Recommendation ITU-T Y.2027 (2012), Functional architecture of multi-connection.
[ITU-T Y.2233] Recommendation ITU-T Y.2233 (2008), Requirements and framework allowing
accounting and charging capabilities in NGN.

[ITU-T Y.2251] Recommendation ITU-T Y.2251 (2011), Multi-connection requirements.

3 Definitions

3.1 Terms defined elsewhere
This Recommendation uses the following terms defined elsewhere:
3.1.1 connection [ITU-T X.200]: A connection is an association established for the transfer of data
between two or more peer-(N)-entities. This association binds the peer-(N)-entities together with the (N-1)-
entities in the next lower layer.
3.1.2 confidentiality [ITU-T X.800]: The property that information is not made available or disclosed to
unauthorized individuals, entities, or processes.
3.1.3 data integrity [ITU-T X.800]: The property that data has not been altered or destroyed in an
unauthorized manner.
3.1.4 denial of service [ITU-T X.800]: The prevention of authorized access to resources or the delaying of
time-critical operations.

3.1.5 mobility [ITU-T Q.1706]: The ability for the user or other mobile entities to communicate and access
services irrespective of changes of the location or technical environment.

3.1.6 multi-connection [ITU-T Y.2251]: The functionality which provides capability to the user equipment
(UE) and network to maintain more than one access network connection simultaneously.

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