Page 526 - 5G Basics - Core Network Aspects

1 Core network aspects

1 Scope
The objective of this Recommendation is to develop a mobility management (MM) framework for
applications involving users with multiple devices. To enable seamless services between those users, it is
required to provide the functions of location management and handover control for a set of devices sharing
a communication session. This Recommendation specifies design considerations, service scenarios,
requirements, functional architecture and information flows for mobility support in applications with
multiple devices.

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 Q.1707] Recommendation ITU-T Q.1707/Y.2804 (2008), Generic framework of mobility
management for next generation networks.
[ITU-T Q.1708] Recommendation ITU-T Q.1708/Y.2805 (2008), Framework of location
management for NGN.
[ITU-T Q.1709] Recommendation ITU-T Q.1709/Y.2806 (2008), Framework of handover
control for NGN.
[ITU-T Y.2018] Recommendation ITU-T Y.2018 (2009), Mobility management and control
framework and architecture within the NGN transport stratum.

3 Definitions

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

3.1.1 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.
3.1.2 mobility management [ITU-T Q.1706]: The set of functions used to provide mobility. These functions
include authentication, authorization, location updating, paging, download of user information and more.
3.1.3 network-based mobility management [ITU-T Q.1707]: A mobility management scheme in which the
MM signalling is performed (or controlled) by the network entities, on behalf of the UE.

3.2 Terms defined in this Recommendation
This Recommendation defines the following terms:

3.2.1 handover: (Definition based on [ITU-T Q.1706]) The ability to provide services with some impact on
their service level agreements to a moving object during and after movement.
3.2.2 multiple devices: A set of individual user devices operated by and connected through the user.
Bundling multiple devices belonging to the user together as a virtual set has the functionality as if there is
only one device rather than multiple devices. One example of the usage using multiple devices is multi-screen
environment. A user can have multiple devices such as TV, PC, mobile phone, digital album, etc. Each device
belonging to the user can compose one logical set with the users. A user sometimes can have more than two

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