Content for TR 24.837 Word version: 10.0.0
5 Protocol evaluation
6 Protocol extensions
7 Extensions to 3GPP TS 24.229
A Definition of protocol extensions
B Example signalling flows
$ Change history
5 Protocol evaluation p. 335
5.1 General p. 335
5.2 Evaluation of solutions for inter-UE transfer and collaborative session procedures for UEs belonging to different IMS subscriptions under the same operator p. 335
5.2.1 Conclusion p. 335
5.3 Discovery of UEs of different IMS subscriptions which can participate in collaborative sessions p. 335
5.3.1 Conclusion p. 335
5.4 Evaluation of solutions for establishment of collaborative session upon session setup p. 335
5.4.0 Conclusion p. 335
5.4.1 Evaluation of solutions for establishment of collaborative session upon originating session setup p. 336
5.4.1.1 Pros and cons of alternative1- indicating collaborative session establishment by providing controllee UE SIP URI in SDP p. 336
5.4.1.2 Pros and cons of alternative2- indicating collaborative session establishment by multipart/related Content-Type parameter p. 336
5.4.1.3 Pros and cons of alternative 3 - indicating collaborative session establishment by providing controllee UE SIP URI in SDP using P-Asserted-Identity p. 336
5.4.2.2 Evaluation of procedures for establishment of collaborative session upon terminating IMS session setup p. 336
5.4.2.2.1 Pros and Cons of Alternative 1 - indicating collaborative session establishment by providing controllee UE SIP URI in SDP p. 336
5.4.2.2.2 Pros and Cons of Alternative 2 - indicating collaborative session establishment by multipart/related Content-Type parameter p. 336
5.4.2.2.3 Pros and Cons of Alternative 3 - indicating collaborative session establishment by SIP REFER request before SIP 200 (OK) response p. 336
5.4.2.2.4 Pros and Cons of Alternative 4 - Using SIP 300 (Multiple Choices) response p. 337
5.5 Evaluation of solutions for transfer of control of a collaborative session p. 337
5.5.1 Conclusion p. 337
5.5.2 Evaluation of procedures for transfer of control of a collaborative session p. 337
5.5.2.1 Indicating whether Controller UE wishes to remain a controller of the collaborative Session p. 337
5.5.2.1.1 Pros and Cons of Alternative 1 - Indicating whether Controller UE wishes to remain a controller of the collaborative Session using the iut-controller media feature tag p. 337
5.5.2.1.2 Pros and Cons of Alternative 2 - Indicating whether Controller UE wishes to remain a controller of the collaborative Session using an XML body p. 337
5.5.2.1.3 Pros and Cons of Alternative 3 - Indicating whether Controller UE wishes to be the controller of the collaborative session using a new media feature tag p. 338
5.5.2.2 Identifying that another UE is requested to become a controller of the collaborative session p. 338
5.5.2.2.1 Pros and Cons of Alternative 1 - Identifying a new controller UE using SIP REFER with method= REFER p. 338
5.5.2.2.2 Pros and Cons of Alternative 2 - Identifying a new controller UE using an XML Body p. 338
5.5.2.2.2.1 General p. 338
5.5.2.2.2.2 Pros and Cons of Alternative 2A - Identifying a new controller UE using SIP INFO p. 338
5.5.2.2.2.3 Pros and Cons of Alternative 2B - Identifying a new controller UE using an Event Package p. 339
5.5.2.2.2.4 Pros and Cons of Alternative 2C - Identifying a new controller UE using XML embedded in Refer-To URI p. 339
5.5.2.2.3 Pros and Cons of Alternative 3 - Identifying a new controller UE using a SIP header field p. 339
5.5.2.2.4 Pros and Cons of Alternative 4 - Identifying a new controller UE using Accept-Contact in the Refer-To URI p. 339
5.5.2.3 Indicating to another UE that it is requested to become a controller of the collaborative Session p. 340
5.5.2.3.1 General p. 340
5.5.2.3.2 Pros and Cons of Alternative 1 - Requesting a UE to become a controller UE using an XML Body p. 340
5.5.2.3.2.1 General p. 340
5.5.2.3.2.2 Pros and Cons of Alternative 1A - Assigning a new controller UE using SIP INFO p. 340
5.5.2.3.2.3 Pros and Cons of Alternative 1B - Assigning a new controller UE using an Event Package p. 340
5.5.2.3.2.4 Pros and Cons of Alternative 1C - Assigning a new controller UE using XML Body as a MIME type in the request p. 340
5.5.2.3.3 Pros and Cons of Alternative 2 - Requesting a UE to become a controller UE using a SIP header field p. 341
5.5.2.3.4 Pros and Cons of Alternative 3 - Requesting a UE to become a controller UE using a media feature tag in an Accept-Contact header field p. 341
5.5.2.4 Indicating acceptance of becoming a controller of the collaborative session p. 341
5.5.2.4.1 Pros and Cons of Alternative 1 - Indicating acceptance of becoming a controller using an XML Body p. 341
5.5.2.4.1.1 General p. 341
5.5.2.4.1.2 Pros and Cons of Alternative 1A - Indicating acceptance of becoming a controller using an XML Body in SIP 200 (OK) response p. 341
5.5.2.4.1.3 Pros and Cons of Alternative 1B - Indicating acceptance of becoming a controller using an XML Body in SIP INFO request p. 341
5.5.2.4.2 Pros and Cons of Alternative 2 - Indicating acceptance of becoming a controller using a SIP header field p. 342
5.5.2.4.3 Pros and Cons of Alternative 3 - Indicating acceptance of becoming a controller using a new feature tag p. 342
5.5.2.5 Informing that another UE has become a controller of the collaborative session p. 342
5.5.2.5.1 Pros and Cons of Alternative 1 - Informing that another UE has become a controller UE using an XML Body p. 342
5.5.2.5.1.1 General p. 342
5.5.2.5.1.2 Pros and Cons of Alternative 1A - Informing that another UE has become a controller UE using SIP INFO p. 342
5.5.2.5.1.3 Pros and Cons of Alternative 1B - Informing that another UE has become a controller UE using a new Event Package p. 342
5.5.2.5.2 Pros and Cons of Alternative 2 - Informing that another UE has become a controller UE using a SIP header field p. 343
5.5.2.5.3 Pros and Cons of Alternative 3 - Informing that another UE has become a controller UE using a SIPfrag in an event package p. 343
5.5.2.5.3.1 Pros and Cons of Alternative 3A - Informing that another UE has become a controller UE using a SIPfrag of the XML body in the response p. 343
5.5.2.5.3.2 Pros and Cons of Alternative 3B - Informing that another UE has become a controller UE using a SIPfrag of the new header field p. 343
5.5.2.5.3.3 Pros and Cons of Alternative 3C - Informing that another UE has become a controller UE using a SIPfrag of a feature tag in the Contact header field p. 343
5.6 Evaluation of solutions for media flows transfer p. 344
5.6.1 Evaluation of solution for media flows transfer by the target UE p. 344
5.6.0 Conclusion p. 344
5.7 Evaluation of solutions for session replication p. 345
5.7.1 Evaluation of solutions for session replication by the SCC AS - pull mode p. 345
5.7.1.1 General p. 345
5.7.1.2 New SDP attribute to indicate replication of media component p. 345
5.7.1.3 New SIP header field, "Replicate", to distinguish a request for replication p. 345
5.7.1.4 New XML body for session and media flow replication p. 346
5.7.1.5 New media feature tag g.3gpp.iut.replicator in Accept-Contact header field p. 346
5.7.1.6 Conclusion on identifying requests for replication by the SCC AS p. 346
5.7.2 Evaluation of solutions for session replication by the SCC AS - push mode p. 346
5.7.3 Evaluation of solutions for session replication by remote UE - pull mode p. 346
5.7.3.0 Conclusion p. 346
5.7.3.1 Pros and cons of alternative 1 (as described in subclause 4.7.2.3.1) p. 346
5.7.3.1A Pros and cons of alternative 1A (as described in subclause 4.7.2.3.1A) p. 347
5.7.4 Evaluation of solutions for session replication by remote UE - push mode p. 347
5.8 Inter-UE transfer between UEs connected to the IMS and UEs in the CS domain p. 347
5.8.0 Conclusion p. 347
5.9 Evaluation of solutions for session discovery p. 348
5.9.0 Conclusion p. 348
5.10 Collaborative session handling upon loss of collaborative session control p. 348
5.10.0 Conclusion p. 348
5.11 Evaluation of solutions for media modification p. 348
5.11.1 Conclusion p. 348
5.12 Collaborative session profile p. 348
5.12.0 Conclusion p. 348
5.13 Evaluation of solutions for inter-UE transfer without establishing a collaborative session p. 348
5.13.0 Conclusion p. 348
5.14 Evaluation of solutions for supplementary services p. 348
5.14.1 Conclusion p. 348
6 Protocol extensions p. 349
6.1 General p. 349
6.2 Definition of media feature tag g.3gpp.iut-focus p. 349
6.3 Replication body p. 349
6.4 Media feature tag g.3gpp.iut.solicit p. 351
6.5 Extension to Contact header field p. 351
7 Extensions to 3GPP TS 24.229 p. 352
7.1 General p. 352
A Definition of protocol extensions p. 352
A.1 Media feature tag g.3gpp.iut-xyz p. 352
A.2 Media feature tag g.3gpp.iut.replicator p. 353
A.3 Media feature tag g.3gpp.current-iut-controller p. 353
A.4 IUT transfer feature XML schema p. 354
A.5 Definition of SDP attribute a=3gpp.iut.controllee p. 355
B Example signalling flows p. 356
B.1 Scope of signalling flows p. 356
B.2 Introduction p. 356
$ Change history p. 357
