Generic Authentication Architecture (GAA); Zh and Zn Interfaces based on the Diameter protocol; Stage 3
The present stage 3 specification defines the Diameter based implementation for bootstrapping Zh interface (BSF-HSS) and Dz interface (BSF-SLF) for HSS resolution for the BSF, the MAP based implementation for bootstrapping Zh' interface (BSF-HLR) and GAA Application Zn interface (BSF-NAF) in Generic Authentication Architecture (GAA). This specification also defines the Web Services based implementation for GAA Application Zn reference point (BSF-NAF). The definition contains procedures, message contents and coding. The procedures for bootstrapping and usage of bootstrapped security association are defined in 3GPP TS 33.220 [5].
The present document also specifies the Diameter and Web Services based implementation for the GAA Application Push Function Zpn reference point (BSF-NAF). The procedures for bootstrapping are defined in 3GPP TS 33.223 [23].
This specification is a part of the Generic Authentication Architecture (GAA) specification series.
The diameter based implementation for the Zh interface is based on re-usage of Cx interface Multimedia-Auth-Request/Answer messages originally between CSCF and HSS. These messages are defined in 3GPP TS 29.229 [3]. The 3GPP IMS mobility management uses the same definitions between CSCF and HSS. The present document defines how the defined messages are used with the bootstrapping and GAA application procedures (e.g. subscriber certificates) and the application logic that is needed in GAA network elements (BSF, HSS, and NAF).
Figure 1.1 depicts the relationships of these specifications to the other specifications for the Diameter based implementations.
Figure 1.1:  Relationships to other specifications
Figure 1.2 provides an informal overall quick introduction to the whole signalling procedures in GAA system. The important identifiers are marked bold and optional data items are italicised. The Ub and Ua interfaces, not defined in this TS, are simplified.
NOTE:	The Zh' interface (BSF-HLR) is not represented in this figure.
Figure 1.2: The whole signalling procedure in GAA system
Figure 1.3 provides an informal overall quick introduction to the whole signalling procedures in GAA Push Function. The important identifiers are marked bold and optional data items are italicised. The Ua and Upa interfaces, not defined in this TS, are simplified.
Figure 1.3: Signalling procedure in GAA Bootstrapping Push Function