The IMS: IP Multimedia Concepts And Services, Second Edition

3.12. User profile

When a user obtains an IMS subscription from an operator, the operator needs to assign a user profile. The user profile contains at least one private user identity and single service profile. Figure 3.19 depicts the general structure of a user profile [3GPP TS 29.228]. The private user identity was described in Section 3.5.1.1, but it should be understood that a user profile may contain more than one private user identity, if a user is using a shared public user identity as described in Section 3.7. Figure 3.4 shows that a single IMS subscription may contain multiple service profiles; this allows different treatment for different public user identities as explained in Section 3.5.1.4.

3.12.1. Service profile

A service profile is a collection of user-specific information that is permanently stored in the HSS. It is transferred from the HSS to an assigned S-CSCF in two user data-handling operations – Server-Assignment-Answer (SAA) and Push-Profile-Request (PPR) – as described in Sections 2.3.4.1 and 2.3.4.2. The service profile is carried in one Diameter AVP, where it is included as an Extensible Markup Language (XML) document. The service profile is further divided into three parts:

• Public Identification;

• Core Network Service Authorization;

• Initial Filter Criteria.

Figure 3.17. IMS charging correlation.

Figure 3.18. Distribution of charging information.