Page 459 - 5G Basics - Core Network Aspects

Core network aspects 1

• the mobile station PAM function maps to the Mobile Station (for simplicity, other MS functions are
not shown);
• CCF/SSF maps to the (G)MSC/VLR/SSP;
• the PAM-SCF functional entity maps to the PAM-SCP;

• the SRF functional entity maps to the IP.
Figure 6 illustrates the scenario of allocating all the PAM service functional entities to the same physical node
when a MSISDN is used as the PAM service number. Note that the CCF and SSF have been mapped to different
nodes. This separation of the CCF and SSF is described in further detail in later clauses.

Figure 6 – Scenario for assigning FEs to the same physical node when
using MSISDN as the PAM service number

In Figure 6, the PAM service functional entities are mapped to one physical node referred to as the PAM
service platform which supports the SSF, SRF and PAM-SCF functionalities.

8 Capability requirements

When a mobile user requests to have legacy PSTN/ISDN access (i.e., the PAM service), the support of user
registration and deregistration, authentication and call handling through the PSTN/ISDN access is required.

8.1 User authentication through PSTN/ISDN access
When a mobile user requests access to the PSTN/ISDN, mutual authentication between the MS PAM function
and the AP function is required.
During registration request processing, authentication needs to be performed. To accomplish user
authentication through a fixed line access, a bearer channel between the AP function via which the MS PAM
function is requesting service and the SRF needs to be set up to enable the PAM-SCF to exchange necessary
identification and authentication information in-band with the AP function.

The support of the same terminal authentication mechanism as used in the mobile network is required: the
AP has to be able to receive the same authentication information from the mobile terminal that the mobile
network RAN would receive as part of the registration procedure, and the AP must be able to relay this to
the PAM-SCF so that the latter may interact with the HLR/AuC (HSS) to complete the registration.

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