Page 474 - 5G Basics - Core Network Aspects

1 Core network aspects

1 Scope
This Recommendation describes an architecture of mobility management and control functions (MMCFs) for
the NGN transport stratum. This architecture includes the definitions of the functional entities of MMCF and
the scenarios for interactions with the other NGN functional components: NACF, RACF, SCF and the access
and core transport functional blocks within the forwarding plane. This Recommendation considers the types
of mobility management described in [ITU-T Q.1706]. This version of the Recommendation is limited to
mobility of a single device, as opposed to the movement of sessions from one device to another (session
mobility). It is further limited, as indicated by the Recommendation title, to support of IP-based mobility in
the transport stratum. In this it differs from [ITU-T Q.1707] in that the latter also considers support of mobility
in the service stratum. This Recommendation provides mechanisms to achieve seamless mobility if network
conditions permit, but does not provide any mechanism to deal with service adaptation if the post-handover
quality of service is degraded from the quality of service before handover.

This Recommendation uses the term "location information". That information is currently limited to logical
location information as defined by clause 6.3.2 of [ITU-T Q.1707]. The management of physical (geographic)
location information is for further study.

This Recommendation assumes that mobility is a service, explicitly specified by parameters in the user service
profile. This Recommendation makes no assumption as to whether the mobility service parameters are
located in the transport user profile or the service user profile, but assumes that they are accessible to the
functional entities that need to use them.
This Recommendation is not dependent on specific access technologies, and supports handover across
different technologies.

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.2012] Recommendation ITU-T Y.2012 (2006), Functional requirements and architecture of
the NGN release 1.
[ITU-T Y.2014] Recommendation ITU-T Y.2014 (2008), Network attachment control functions in next
generation networks.
[ITU-T Y.2111] Recommendation ITU-T Y.2111 (2008), Resource and admission control functions in
next generation networks.
[IETF RFC 4282] IETF RFC 4282 (2005), The Network Access Identifier.

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