Page 436 - 5G Basics - Core Network Aspects

1 Core network aspects

Appendix I

FMC approach and scenarios
(This appendix does not form an integral part of this Recommendation)

NGN gives the framework to provide FMC service capabilities irrespective of the different access
technologies. Service providers may also provide FMC services based on existing networks they operate by
changing or upgrading selected components of their network. Different approaches are required to obtain
the ability to provide the desired FMC service experience to users.
End users are able to use FMC services from both the fixed access network and from the mobile access
network.
An example FMC solution is a single multi-mode terminal device, which supports both fixed and mobile access
can provide the user a better service experience, than when using different terminal devices to achieve the
same service result. However, multi-mode terminals may not be able to fully support all necessary access
networks.

Several scenarios for network implementation to achieve FMC services are given in the following clauses.
The transport network is not explicitly shown in these figures. FMC may also support seamless mobility in
transport network between heterogeneous access networks, so the service continuity between these access
transport networks can be achieved. From the service aspect, a multi-mode terminal attached to different
access transport networks may access unified and consistent services and applications. From the network
aspect, mobility-enabled transport network may support any type of IP-based access transport network
regardless of its mobility features. Transport network convergence is for further study.

I.1 Convergence in the control layer
In this scenario, a unified control layer network is provided to support both fixed and mobile access. This
convergence occurs in the control layer as shown in Figure I.1. In this architecture, both the fixed access
network and the mobile access network are controlled by this unified control layer network enabling the
same applications/service support functions to be adopted for the network.

Figure I.1 – Scenario: Convergence in service control functions

NOTE – IMS-based solution described in [ITU-T Y.2021] uses the access-independent IMS network to support different
accesses to provide FMC services. The UMA solution [b-ETSI TS 143 318] uses the unified GSM/UMTS network to provide
FMC services.

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