Canonical Atlas record
IP multimedia call control protocol based on Session Initiation Protocol (SIP) and Session Description Protocol (SDP); Stage 3
IMS SIP/SDP signalling
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Release evolution
Use indexed version, Work Item and Change Request evidence to see what changed around this specification. This is an evidence trail, not a clause-by-clause normative diff.
Release ledger
Rel-16 snapshot
261 indexed Change Requests · 5 connected Work Items.
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Version history
Showing 60 of 428 indexed versions.
Atlas classifications
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Work Items
Rel-4 Emergency call enhancements
Rel-4 Charging and OAM&P
Rel-4 Terminal interfaces
IETF: RFC 3262 (Reliability of provisional responses)
IETF: RFC 3323 (SIP extensions for caller identity and privacy)
IETF: RFC 3312 (Without COMET)(Integration of resource management and SIP)
IETF: RFC 3261 (Session Initiation Protocol)
Main IETF dependencies
Impact on HSS
Architectural issues
Addressing
IETF: RFC editor Queue (Various 3GPP Private Extensions)
IETF: RFC 3324 (Network Asserted Identity)
IETF: RFC 3311 (The Update method)
IETF: RFC 3266 (IPv6 support within SDP)
IETF: RFC 3267 (AMR and AMR WB RTP and SDP)
IETF: RFC editor Queue (DHCP options for SIP servers)
IETF: RFC editor Queue (refer method)
IETF: RFC 3265 (specific event notification)
IETF: RFC 3313 (SIP extensions for media authorization)
E2E QoS interworking
SIP Call Control protocol for the IMS
IMS stage 3
Provisioning of IP-based multimedia services
Call control and roaming to support IMS in UMTS
Impact on MM/CC/SM
Rel-5 Charging Management & Operations, Administration, Maintenance and Provisioning (OAM&P)
(Small) Technical Enhancements and Improvements for Rel-5
Rel-5 Terminal interfaces
Deleted - Stage 2 of IMS Phase 2
Stage 2 for Presence Capability
Interworking between IMS and IP networks
IMS Phase 2
Interoperability and Commonality between IMS using different IP-connectivity Networks
Rel-6 Operations, Administration, Maintenance and Provisioning (OAM&P)
Presence Capability
Study on Security for early IMS
Rel-6 Security enhancements
(Small) Technical Enhancements and Improvements for Rel-6
WLAN-UMTS Interworking Rel-6
Stage 3 - CN4 aspects
CT1 aspects of Mp
Stage 3 for CSICS CN aspects
Combinational Services
Deleted - Study on Terminating Session handling
CSI Terminating Session handling
CT1 IMS aspects to support IMS Emergency sessions
Emergency Call Enhancements for IP& PS Based Calls stage 3
PS domain and IMS impacts for supporting IMS Emergency calls (EMC1)
CT1 aspects for SMSIP
Deleted - duplicated with UID 340015 -Stage 3 CSI Terminating Session handling
Stage 3 of CStermS
Deleted - CT3 aspects of Stage 3 for Voice Call Continuity between CS and IMS (incl. I-WLAN)
CT1 aspects of Stage 3 for Voice Call Continuity between CS and IMS (incl. I-WLAN)
Stage 3 for Voice Call Continuity between CS and IMS (incl. I-WLAN)
Stage 2 for Voice Call Continuity between CS and IMS (incl. I-WLAN)
Stage 1 for Voice Call Continuity between CS and IMS (incl. I-WLAN)
TR for Voice Call Continuity between CS and IMS (incl. I-WLAN)
Protocol impact of FBI for TISPAN R1
CT1 aspects of FBI for TISPAN R1
System enhancements for Fixed Broadband access to IMS
PacketCable Related aspects
Supporting Globally Routable User Agent URIs in IMS
Stage 3 of GRUU
Stage 1,2 of GRUU
IMS Stage 3 IETF Protocol Alignment
IMS Support of Conferencing
Maintenance of TISPAN R1
Rel-7 Operations, Administration, Maintenance and Provisioning (OAM&P)
Rel-7 Trace Management
Evolution of Policy Control and Charging
Rx reference point for PCC CT3 aspects
PCC-Rx CT1 aspects
PCC-Rx CT3 aspects
Support of SMS over generic 3GPP IP access
Identification of Communication Services in IMS
Stage 3 of ServID
(Small) Technical Enhancements and Improvements for Rel-7
Voice Call Continuity between CS and IMS (incl. I-WLAN)
Customized Alerting Tone (CAT) service
IMS CAT Supplementary Service
Call Completion on Busy Subscriber (CCBS)/Call Completion on Non-Reachable (CCNR) on IMS
CT3 part of Stage 3 CCBS_CCNR
CT1 part of Stage 3 CCBS_CCNR
CT3 part of Stage 3 CW-IMS
Communication Wait on IMS
CT1 part of Stage 3 CW-IMS
Study on 3GPP System Architecture Evolution
CT3 aspects - Stage 3 for ICSRA
CT4 aspects - Stage 3 for ICSRA
(IETF) CT4 aspects - Stage 3 for ICSRA (RFC 7254)
Deleted - Stage 3 for ICSRA I1 interface
Stage 3 for ICSRA Protocol, Addressing, Subscriber Data
CT1 aspects - Stage 3 for ICSRA
(IETF) CT1 aspects - Stage 3 for ICSRA (draft-ietf-salud-alert-info-urns)
(IETF) CT1 aspects - Stage 3 for ICSRA (RFC 6871)
(IETF) CT1 aspects - Stage 3 for ICSRA (RFC 7195)
Stage 1 for ICS Requirement and Architecture
(IETF) CT1 aspects - Stage 3 for ICSRA (RFC 7006)
IMS Centralized Service control
Stage 3 IMS Service Continuity
IMS Service Continuity
Security Enhancements for IMS
IMS Stage 3 IETF Protocol Alignment - phase 2
(IETF) IMS Stage 3 IETF Protocol Alignment (draft-ietf-salud-alert-info-urns)
(IETF) IMS Stage 3 IETF Protocol Alignment (RFC 6544)
(IETF) IMS Stage 3 IETF Protocol Alignment (draft-bakker-sipping-3gpp-ims-xml-body-handling)
CT1 aspects of IMS Stage 3 IETF Protocol Alignment - phase 2
CT4 aspects of IMS_Corp
SA1 aspects of IMS_Corp
IMS System enhancements for corporate network access
CT1 aspects of IMS_Corp
System enhancements for interconnection interfaces between two IMSs
IMS Restoration Procedures
IMS Restoration Procedures (CT1)
Maintenance of TISPAN R2
CT1 part of Stage 3 for MESSIW
Service-Level Interworking for Messaging Services
Study on AS-MRFC media server control protocol
AS/MRFC Stage 2 and 3
AS/MRFC Stage 3
AS/MRFC Stage 2
Deleted - CT1 part of Enhancement of interworking between MTSI and CS networks
CT1 part of Network Attachment Subsystem (NASS) Bundled Authentication
Rel-8 Operations, Administration, Maintenance and Provisioning (OAM&P)
IRP SOAP Solution Sets
Alignment with eTOM and M.3060 architectural concepts
CT4 part of Service Level Tracing in IMS
Rel-8 Trace Management
CT1 part of Service Level Tracing in IMS
Deleted - CT3 part of Service Level Tracing in IMS
Stage 3 Overlap (CT1)
Stage 3 Overlap (CT3)
Support of Overlap signalling
CT1 aspects of Stage 3 PNM
Multimedia Priority Service
CT1 part of Stage 3 for PRIOR
IMS Enhancements for support of Packet Cable access
CT1 aspects of PktCbl-Deploy
CT1,CT3 aspects of PktCbl-Interwork
IMS Inter-working aspects in Support of Cable Regulatory requirements
Architecture aspects of PktCbl-Interwork
IMS Enhancements for Security Requirements in Support of Cable Deployments
SA3 aspects of PktCbl-Sec
CT1 aspects of PktCbl-Sec
CT3 aspects of PktCbl-Sec
Stage 3 CIMS_3GPP2 (CT1)
Documentation of TISPAN R1 and R2 in CT1
3GPP System Architecture Evolution Specification - Evolved Packet System (non RAN aspects)
Stage 3 (CT1) for SAE impact on services, network functions and capabilities
(Small) Technical Enhancements and Improvements for Rel-8
Interworking between User-to-User Signalling (UUS) and SIP
CT1 part of Stage 3 MGCF UUSIW
(IETF) Stage 3 MGCF UUSIW (cuss-sip-uui)
CT3 part of Stage 3 MGCF UUSIW
Definition of Ml interface for Control Plane LCS (Stage 3)
CT1 aspects of IMS Stage 3 - IETF Protocol Alignment - phase 3
IMS Stage 3 IETF Protocol Alignment - phase 3
Support for IMS Emergency Calls over GPRS and EPS
CT1 aspects of SRVCC support for IMS Emergency Calls
CT1 aspects - Stage 3 for IMS Emergency Calls over GPRS and EPS
Stage 3 - IMS Centralized Services support via I1 interface
Stage 3 for IMS Service Continuity Enhancements: Service, Policy, Interactions and Inter UE Transfer
IMS Media Plane Security
CT1 aspects of IMS Media Plane Security
CN aspects of IMS Media Plane Security
Service Specific Access Control in EPS
(Small) Technical Enhancements and Improvements for Rel-9
Stage 3 for Enhancements of IMS Customized Alerting Tone (CAT) Service
CT1 aspects of Completion of IMS Restoration Procedures
CT1 part of CN aspects of Enabling Coder Selection and Rate Adaptation for UTRAN and E-UTRAN for Load Adaptive Applications
Stage 3 for IMS Emergency Session Enhancements
IMS Emergency Session Enhancements
CT1 part of UICC access to IMS Specification
UICC access to IMS Specification
IMS Stage 3 IETF Protocol Alignment - phase 4
Stage 3 - IMS Inter-UE Transfer enhancements
IMS Service Continuity Inter Device Transfer enhancements
CT1 part of Stage 3 for Optimal Media Routeing
Optimal Media Routing
Deleted - Registration in Densely-populated area (RED)
(Small) Technical Enhancements and Improvements for Rel-10
(IETF) (Small) Technical Enhancements and Improvements for Rel-10 (draft-atarius-dispatch-meid-urn) --> RFC8464
CT1 part on Stage 3 on enhancements for Multimedia Priority Service
Single Radio Voice Call Continuity (SRVCC) enhancements (Stage 3)
CT1 part of Stage 3 for SRVCC enhancements
CT1 part of Stage 3 BB I: BBF interworking with home routed traffic for WLAN and H(e)NB
Support of RFC 6140 in IMS
CT1 part of IMS Stage 3 IETF Protocol Alignment - phase 5
IMS Stage 3 IETF Protocol Alignment - phase 5
CT1 part of Stage 3 for IMS Overload Control
Stage 3 for Transit Inter Operator Identifier for IMS Interconnection Charging in multi operator environment
CT1 part of Stage 3 for Advanced IP Interconnection of Services
CT1 part of Enhanced T.38 FAX support
CT1 part of Stage 3 for Inclusion of Media Resource Broker
Stage 3 for Inclusion of Media Resource Broker
Network-provided Location information for IMS (NETLOC)
CT1 part of CT aspects of Network-provided Location information for IMS
Roaming Architecture for Voice over IMS with Local Breakout
CT1 part of CT aspects of Roaming Architecture for Voice over IMS with Local Breakout
CT aspects of Roaming Architecture for Voice over IMS with Local Breakout (Stage 3)
Reference Location Information (Stage 3)
CT1 part of Reference Location Information (Stage 3)
SAE Protocol Development (Stage 3) - Phase 2
CS Fallback in EPS - Phase 2
(Small) Technical Enhancements and Improvements for Rel-11
CT1 part of Stage 3 for USSD simulation service in IMS
Stage 2/3 for Support for 3GPP Voice Interworking with Enterprise IP-PBX
CT1 part for Single Radio Voice Call Continuity from UTRAN/GERAN to E-UTRAN/HSPA
CT1 part of Support of ALT-C attribute
CT1 part of CT aspects of IMS Business Trunking for IP-PBX in Static Mode of Operation (Stage 3)
CT1 part of CT aspects of Coordination of Video Orientation
CT1 part of CT aspects of End-to-End Multimedia Telephony Service for IMS (MTSI) extensions
CT1 part of IMS Emergency PSAP Callback
IMS Emergency PSAP Callback (Stage 3)
CT1 part of CT impacts of codec for Enhanced Voice Services
Study on Coordinated Multi-Point (CoMP) operation for LTE with Non-Ideal Backhaul
CT1 part of Impacts of RFC7044 for introduction of the new History-Info header field
CT1 part of IMS Stage 3 IETF Protocol Alignment - phase 6
IMS Stage 3 IETF Protocol Alignment - phase 6
Deleted - CT1 aspects of CT aspects of IMS registration control (Stage 2/3)
CT1 part of IMS Telepresence (Stage 3)
CT1 part of CT aspects of Web Real Time Communication (WebRTC) Access to IMS
CT1 part of Network-provided Location information for IMS Trusted WLAN Access Network (TWAN) case
CT1 part of Indication of NNI Routeing scenarios in SIP requests
CT1 part of HSS based solution
CT1 part of PCRF based solution
CS Fallback in EPS - Phase 3
SAE Protocol Development (Stage 3) - Phase 3
SAE for support for non-3GPP accesses - Phase 3
CT1 part of CT Aspects of Signalling of Image Size
(Small) Technical Enhancements and Improvements for Rel-12
Tunneling of UE Services over Restrictive Access Networks (Stage 2/3)
CT aspects of Tunneling of UE Services over Restrictive Access Networks (Stage 3)
Updating IMS to conform to RFC 6665 (Stage 3)
CT1 part of Updating IMS to conform to RFC 6665
Network Initiated USSD Simulation Services in IMS
CT1 part of IMS Operator Determined Call Barring enhancements
Extended IMS media plane security features
CT1 part of CT aspects of Extended IMS media plane security features
Double Resource Reuse for Multiple Media Sessions
Awaiting formal work item
IMS Stage-3 IETF Protocol Alignment
CT1 part of Support of RTP / RTCP multiplexing (signalling) in IMS
SAE for support for non-3GPP accesses - Phase 4
(Small) Technical Enhancements and Improvements for Rel-13
Stage 3 for Enhancements to WebRTC interoperability
CT1 part of CT aspects of voice over E-UTRAN Paging Policy Differentiation
CT1 part of IMS Signalling Activated Trace
CT Aspects of RobVoLTE
SAES5 for support for non-3GPP accesses
CT aspects of SEW2
Stage 3 of User Controlled Spoofed Call Treatment
(Small) Technical Enhancements and Improvements for Rel-14
CT Aspects of V8
5G System - Phase 1
CT aspects of 5G System - Phase 1
Historical association · verification pendingIMS Stage-3 IETF Protocol Alignment
Media Handling Extensions for 5G Conversational Services
Wireless and Wireline Convergence for the 5G system architecture
Historical association · verification pendingProvision of Access to Restricted Local Operator Services by Unauthenticated UEs
(Small) Technical Enhancements and Improvements for Rel-16
5GS Enhanced support of Vertical and LAN Services
Historical association · verification pendingStage-3 5GS NAS protocol development 17
Historical association · verification pendingCT aspects of 5GC architecture for satellite networks
Historical association · verification pendingProximity based Services in 5GS
Historical association · verification pendingArchitecture Enhancement for NR Reduced Capability Devices
IMS Stage-3 IETF Protocol Alignment
Multimedia Priority Service (MPS) Phase 2
Support for Multi-USIM Devices
Historical association · verification pendingMulti-device enhancements for device transfers
Modifying PASSporT signing and verification for Spoofed calls
(Small) Technical Enhancements and Improvements for Rel-17
Support for Signed Attestation for Priority and Emergency Sessions
Enhancement for the 5G Control Plane Steering of Roaming for UE in Connected mode
Historical association · verification pendingEnhancements of 3GPP profiles for cryptographic algorithms and security protocols
Enhanced support of Non-Public Networks
Historical association · verification pendingStage-3 5GS NAS protocol development 18
Satellite access Phase 2
Proximity-based Services in 5GS Phase 2
IMS Stage-3 IETF Protocol Alignment
System architecture for Next Generation Real time Communication services
NR RedCap UE with long eDRX for RRC_INACTIVE State
(Small) Technical Enhancements and Improvements for Rel-18
Non-Public Networks Phase 2
Stage-3 5GS NAS protocol development 18
Historical association · verification pendingCT aspects of integration of satellite components in the 5G architecture Phase 3
IMS Stage-3 IETF Protocol Alignment
IMS Disaster Prevention and Restoration Enhancement
MPS for Messaging services
System architecture for Next Generation Real time Communication services Phase 2
(Small) Technical Enhancements and Improvements for Rel-19
Alignment of eCall over IMS with CEN
CT aspects for integration of satellite components in the 5G Phase 4
IMS Stage-3 IETF Protocol Alignment
Protocol enhancements for Mission Critical Services
CT aspects of Next Generation Real Time Communication Services Phase 3
(Small) Technical Enhancements and Improvements for Rel-20
General Packet Radio Service
Lawful Interception for GSM Features transposed to UMTS
OAM Principles and High-level Requirements
UICC / Terminal interface; Physical and logical characteristics
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