Page 467 - 5G Basics - Core Network Aspects

Core network aspects 1

26b. After the AP receives the registration response, the AP ends the registration process by releasing
the call.
27b. A release call message is sent to the (MSC/VLR)/SSP.
28b. The (MSC/VLR)/SSP ends with the release complete confirmation.

29. The (MSC/VLR)/SSP reports the event to the PAM-SCP.
30. The PAM-SCP finishes the dialogue with the (MSC/VLR)/SSP.
9.3.2 User deregistration call flow

Mobile Access PSTN (MSC/VLR) PAM-SCP IP HLR/AuC
station point switch /SSP (HSS)
1. Automatic call
set up (SAC-
Service deregister request type,
request terminal identifier) 2. Set up request- 3. Query (triggered by N-CSI)
4. Deactivate the PAM service
5. Deactivate ack
6. Prepare special resource
7. Establish connection with special resource
9. Set up response- 8. Special resource connected
10. Special resource ready
11. Send deregistration response
Service deregister
response 12. Send deregistration response in FSK
14a. Release the special resource 13. Result of sending response
15a. Release
14 . On hookb 16a. Release complete
15b. Release
16b. Release complete
17. Report release event
18. End of query
Q.1763/Y.2803(07)_F09

Figure 9 – User deregistration call flow
1. When the terminal leaves the wireless coverage area of the AP, the AP sends a deregistration
request to the network by means of a call set-up request containing the SAC, request type (indicating
deregistration) and the terminal identifier of the terminal.

2. The PSTN switch routes the call set-up request to the (MSC/VLR)/SSP according to the SAC.
3. The (MSC/VLR)/SSP triggers and sends a query to the PAM-SCP. The node (MSC/VLR)/SSP is currently
exercising IN SSP functionality only. MSC/VLR functions are not used in this scenario.

4. The PAM-SCP sends a request to the HLR/AuC (HSS) to deactivate the user's PAM service.
5. The HLR/AuC (HSS) responds with the result of the deactivation and the PAM-SCP deletes the service
data.

6. The PAM-SCP instructs the (MSC/VLR)/SSP to set-up a bearer connection to the IP to prepare the
special resource for FSK interaction.
7. The (MSC/VLR)/SSP sets up a connection with the IP via ISUP signalling.

8. The IP acknowledges the (MSC/VLR)/SSP with a connection established response.
9. The connection set-up response is forwarded to the PSTN switch and the connection is set up
between the AP and the IP.
10. The IP sends its availability and capability to the PAM-SCP.
11. The PAM-SCP instructs the IP to send a "Deregistration response" (in FSK) to the AP.

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