This reference point provides mutual authentication between the
UE and the BSF. It allows the UE to bootstrap the session keys based on 3GPP AKA infrastructure.
The HTTP Digest AKA protocol, which is specified in
RFC 3310, is used on the reference point Ub. It is based on
the 3GPP AKA
TS 33.102 protocol. The interface to the USIM is as specified in
and to the ISIM is as specified in
The GBA-Push related to the Upa interface is between a NAF and UE. GBA-Push is a mechanism to bootstrap the
security between a NAF and a UE, without forcing the UE to contact the BSF to initiate the bootstrapping.
This interface enables the user to manage information related to his services. Such as creation and assignment of Public Service Identities, management of authorization policies that are used e.g. by Presence service, conference policy management, etc.
The AS may need to exhibit security related functions for the Ut interface, the details of these security functions are described in TS 33.222.
For the protocol at the Ut reference point, HTTP shall be supported.