Page 359 - 5G Basics - Core Network Aspects

Core network aspects 1

The extended service control function (SCF) maintains multi-connection in the session layer and is responsible
for the session continuity when the service is transferred among different connections so that the SEID is
recommended to be maintained in the SCF to handle the session layer multi-connection management.

Finally, the extended multi-connection application support function (MAS-F) is responsible to support
between applications and the SCF, and the SVID is recommended to be maintained in the MAS-F.

8 Resource identifiers in multi-connection network

8.1 Introduction of resource IDs according to multi-connection scenarios

This clause describes examples of the usage of resource IDs according to multi-connection scenarios
described in [b-ITU-T Y-Sup.9].

1) Scenario A
An MUE accesses an access network simultaneously via multiple frequency bands. Because a single access
network is served, and one ANID is used to identify it, multiple IFIDs for logical/virtual interfaces are also
used to distinguish multiple frequency bands.

2) Scenario B
An MUE can access multiple access networks simultaneously using the same access technology. One ANID
for an access technology is used because a single access control function is supported in this scenario.
Multiple IFIDs for the physical interfaces are also used to distinguish many access networks.
3) Scenario C

An MUE connects to heterogeneous access networks, which are controlled by different access control
functions. Therefore, multiple ANIDs and IFIDs are used to distinguish different access networks and access
control functions. One SEID is used in the service control function.
4) Scenario D

An MUE connecting to multiple heterogeneous access networks is controlled by separate access control and
service control functions using multiple ANIDs, IFIDs and SEIDs. One SVID is used in the application.
5) Scenario E

An MUE connects to multiple heterogeneous access networks through multiple access points, which are
controlled by separate access control and service control functions for different applications. Here, multiple
ANIDs, IFIDs, SEIDs and SVIDs are used at the same time.

8.2 Introduction of resource IDs according to multi-connection use cases
This clause describes the usage of resource IDs in multi-connection use cases described in [ITU-T Y.2027].

8.2.1 Initiating the services of application
If an MUE is using multiple connections to support an application with several service components, one or
more SVIDs represent the application or service components. Here, a connection, served by a SEID and a
FLID, is mapped and maintained to support each service component. This clause describes initiation and
addition of multiple connections by using resource IDs.
a) An MUE attaches an access network with an IFID and an ANID. After access authorization, the MUE
will get an IP address and then allocate it to the interface connecting to the access network.
b) An MUE selects a SVID to identify the application with several service components. After getting
information of a peer MUE, the MUE connects to the peer MUE. A connection is distinguished by
using SEID and FLID.
c) An MUE gets a new IP address and assigns IFID and ANID to identify access networks and interfaces
after completion of the authorization procedure of new access network authority. And then, the
MUE binds the FLID to its access related resource IDs such as IFIDs and ANIDs, and their information
is delivered to the MR-FE.

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