A1.3 Signalling flows demonstrating a successful GBA Push procedure

24.1093GPPBootstrapping interface (Ub) and network application function interface (Ua)Protocol detailsRelease 17TS

The overall GBA Push procedure in the successful case is presented in figure A1.3-1. The bootstrapping interface Zh performs the retrieval of an authentication vector by BSF from the HSS, this corresponds to steps 4 and 5 in figure A1.3-1. The bootstrapping interface Zpn performs the retrieval of the GPI by the Push-NAF from the BSF, this corresponds to steps 2 and 7 in figure A1.3-1. The bootstrapping interface Upa is used to transfer the GPI from the Push-NAF to the UE, this corresponds to step 9 in figure A1.3-1. The Zpn interface is defined in 3GPP TS 29.109 [3].

Figure A1.3-1: GBA Push signalling

1. Generate GPI Request (Push-NAF)

A Push-NAF needs to establish a shared NAF SA with a UE which is registered for Push services. It knows the identity of the subscriber. The Push-NAF performs the processing described in 3GPP TS 33.223 [24] and generates the GPI Request.

2. Send GPI Request (Push-NAF to BSF)

The Push-NAF sends the GPI Request to the BSF.

3. Initial processing of GPI Requestion (BSF)

Upon receiving the request from the NAF, the BSF performs the processing steps described in 3GPP TS 33.223 [24].

4-5. Zh: Authentication procedure (BSF and HSS)

These steps correspond to Step 2 in figure A.3-1.

6. NAF SA generation (BSF)

The BSF generates the NAF SA as defined in 3GPP TS 33.223 [24].

7. Send GPI Response (BSF to Push-NAF)

The GPI Response generated in the previous step is sent from the BSF to the Push-NAF.

8. NAF SA storage (Push-NAF)

The Push-NAF stores the information needed to maintain the NAF SA as described in 3GPP TS 33.223 [24].

9. GPI Push (Push-NAF to UE)

The Push-NAF sends a GPI Push to the UE. This can be send over whatever transport method that the Push-NAF wishes to use (e.g. SMS, MMS, SIP Message, etc) The GPI Push message is described in 3GPP TS 33.223 [24].

10. NAF SA Storage (UE)

The UE processes the GPI as described in 3GPP TS 33.223 [24] and stores the NAF SA. The UE does not need to contact the network to correctly generate the NAF SA.

Annex B (informative):
Signalling flows for HTTP Digest Authentication with bootstrapped security association