E.3 Call flow with IMEI check in VPLMN

29.2733GPP3GPP EPS AAA interfacesEvolved Packet System (EPS)Release 18TS

Figure Annex E.3-1 describes a roaming call flow, with IMEI check performed in the VPLMN.

Figure Annex E.3-1: Untrusted WLAN Authentication and Authorization Procedure, with IMEI check performed in the VPLMN

1. to 5. Same as Figure E.2-1.

6. If IMEI check is required by operator policy, the ePDG requests the UE to provide its Mobile Equipment Identity.

7. Same as Figure E.2-1.

8. The ePDG includes the Terminal-Information AVP in the DER command. If IMEI check is required by operator policy, the 3GPP AAA Proxy performs the IMEI check in the VPLMN. If the IMEI check allows to continue the authentication and authorization procedure, the 3GPP AAA Proxy forwards the DER to the 3GPP AAA Server (as shown in this figure). Otherwise the 3GPP AAA Proxy responds to the ePDG with the Experimental-Result-Code DIAMETER_ERROR_ILLEGAL_EQUIPMENT and sends a SWm Session Termination Request towards the 3GPP AAA Server.

9 to 17. Same as Figure E.2-1 if the IMEI check in VPLMN was successful.

Annex F (normative):
Diameter load control mechanism