123380 «FRESH · Review»

For further technical reading, the latest versions (such as ) are available via the ETSI Deliverable Repository . ETSI TS 123 380 V9.6.0 (2014-03)

: Procedures for recovering the Home Subscriber Server, which acts as the central database for user identities and profiles.

The specification has evolved through multiple "Releases" to keep pace with mobile technology: 123380

: Procedures for when a Serving-Call Session Control Function (S-CSCF) fails or loses registration data. It defines how the Home Subscriber Server (HSS) and other nodes collaborate to re-register users or restore sessions.

: During initial registration, the S-CSCF backs up critical data—such as the list of SIP proxies, contact information, and authentication schemes—to the HSS. For further technical reading, the latest versions (such

: These are specific Diameter protocol messages (Server-Assignment-Request and Location-Information-Request) used by the HSS and S-CSCF to update and overwrite user data during restoration events.

: Focused on basic IMS recovery for GSM and UMTS. It defines how the Home Subscriber Server (HSS)

: Nodes use indicators (often via IETF RFC 6223) to detect the availability of peers and trigger restoration if a failure is detected. 4. Evolution and Versions