1. IMS Overview

2. IMS Architecture

2.1 Session Management and Routing
2.1.1. The Proxy CSCF
2.1.2. The Interrogating CSCF
2.1.3. The Serving CSCF
2.1.4. The Emergency CSCF
2.1.5. CSCF interfaces
2.2. Databases
2.2.1. The Home Subscriber Server
2.2.2. Subscription Locator Function
2.3. Services Elements
2.3.1. MMTel AS
2.3.2. SCC AS
2.3.3. IP-SM-GW AS
2.3.4. IM SSF AS
2.4. Inter-working Elements
2.4.1. The Breakout Gateway Control Function
2.4.2. The Interconnection Border Control Function
2.4.3. The Media Gateway Control Function

3. IMS specific identifiers

3.1. Public user identities
3.1.1. SIP URI
3.1.2. TEL URI
3.2. Private User Identity
3.3. Relation between Private and public User identity
3.4. Public Service Identity
3.5. IRS
3.6. ISIM