A.7.4 Controllee UE releases media
24.3373GPPIP Multimedia (IM) Core Network (CN) subsystem IP Multimedia Subsystem (IMS) inter-UE transferRelease 17Stage 3TS
Figure A.7.4: Controllee UE releases media
NOTE 1: For clarity, the SIP 100 (Trying) responses are not shown in the signalling flow.
It is assumed that UE-1 is controller UE having collaborative session control. a user has a multimedia session on his device UE‑1 with voice (Media A) and UE-2(Controllee UE) video (Media B) media flows. Subsequently, the UE-2 (Controllee UE) removes the media B flow that is active on the remote UE.
1-2. SIP re-INVITE request (UE-2 to SCC AS through IM CN subsystem entities)
A UE-2 wants to release media B active on the remote UE. For this purpose the UE-2 sends a SIP re-INVITE request to the SCC AS through the IM CN subsystem entities.
3. SIP re-INVITE request (from SCC-AS to intermediate IM CN subsystem entities) – see example in table A.14.4-3
The SCC AS sends SIP re-INVITE request to controller UE, UE-1 to inform that the controllee UE wants to release one media, and SCC AS would like to add this media back to the controller UE.
Table A.7.4-3: SIP re-INVITE request (SCC AS to controller UE)
INVITE <sip:user1_public1@home1.net;gr=urn:uuid:f81d4fae-7dec-11d0-a762-00a0c91e6bf6> SIP/2.0
Via: SIP/2.0/UDP sccas1.home1.net;branch=z9hG4bKnas34r2.12
Max-Forwards: 70
Route: <sip:orig@scscf1.home1.net;lr>
P-Asserted-Identity: "John Doe" <sip:user3_public3@home3.net>
Privacy: none
From:
To:
Call-ID:
Cseq: 127 INVITE
Require:
Contact: <sip: user3_public3@home3.net>; gr=urn:uuid:f81d4fae-7dec-11d0-a765-00a0c67t6br4>
Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE, REFER, MESSAGE, SUBSCRIBE, NOTIFY
Content-type: application/sdp
Content-Length: (…)
v=0
o=- 2987933615 2987933615 IN IP6 3333::aaa:bbb:ccc:ddd
s=-
t=0 0
m=audio 5555 RTP/AVP 97
c=IN IP6 3333::aaa:bbb:ccc:ddd
a=rtpmap:97 PCMU/90000
m=video 3000 RTP/AVP 98
c=IN IP6 4444::aaa:bbb:ccc:ddd
a=rtpmap:98 MPV/90000
4. SIP re-INVITE request (intermediate IM CN subsystem entities to controller UE, UE-1)
5. SIP 200 (OK) response (controller UE, UE-1 to intermediate IM CN subsystem entities) – see example in table A.7.4-5
In this case, the controller UE does not want to add this media on itself, but like to delete this media within the collaborative session. The controller UE cknowledges the SIP re-INVITE request by sending SIP 200 (OK) response to the SCC AS with the port number set to zero for this media.
Table A.7.4-5: SIP 200 (OK) (controller UE to SCC AS)
SIP/2.0 200 OK
Via:
From:
To:
Call-ID:
Cseq:
Contact: <sip: user1_public1@home1.net>; gr=urn:uuid:f81d4fae-7dec-11d0-a765-00a0c43t6br4>;+g.3gpp.iut-controller
Allow:
Content-Type: application/sdp
Content-Length: (…)
v=0
o=- 2987933300 2987933300 IN IP6 5555::aaa:bbb::ccc:ddd
s=-
c=IN IP6 5555::aaa:bbb::ccc:ddd
t=0 0
m=audio 4444 RTP/AVP 97
a=rtpmap:97 PCMU/8000
m=video 0 RTP/AVP 98
a=rtpmap:98 MPV/9000
6. SIP 200 (OK) response (intermediate IM CN subsystem entities to SCC AS)
7-8.SIP ACK (SCC AS to controller UE)
9. SIP re-INVITE request (SCC AS to intermediate IM CN subsystem entities)-see example in table A.7.4-9
The SCC AS sends a SIP re-INVITE request to update the remote leg that the media B is released.
Table A.7.4-9: SIP re-INVITE request (SCC AS to intermediate IM CN subsystem entities)
INVITE <sip:user3_public3@home3.net;gr=urn:uuid:f81d4fae-7dec-11d0-a762-00a0c91e6bf6> SIP/2.0
Via: SIP/2.0/UDP sccas1.home1.net;branch=z9hG4bKnas34r2.12
Max-Forwards:
Route: <sip:orig@scscf1.home1.net;lr>
P-Asserted-Identity: "Jake" <sip:user1_public1@home1.net>
Privacy: none
From: <sip:user1_public1@home1.net>;tag=171828
To: <sip:user3_public3@home3.net>;tag = 66666
Call-ID: cb03a0s09a2sdfglkj490333
Cseq: 127 INVITE
Supported: 100rel, precondition
Contact: <sip: user1_public1@home1.net>; gr=urn:uuid:f81d4fae-7dec-11d0-a765-00a0c43t6br4>
Allow: INVITE, ACK, CANCEL, BYE, PRACK, UPDATE, REFER, MESSAGE, SUBSCRIBE, NOTIFY
Accept: application/sdp
ontent-Type: application/sdp
Content-Length: (…)
v=0
o=- 2987933615 2987933615 IN IP6 3333::aaa:bbb:ccc:ddd
s=-
t=0 0
m=audio 5555 RTP/AVP 97
c=IN IP6 3333::aaa:bbb:ccc:ddd
a=rtpmap:97 PCMU/90000
m=video 0 RTP/AVP 98
c=IN IP6 4444::aaa:bbb:ccc:ddd
a=rtpmap:98 MPV/90000
10. SIP re-INVITE request (intermediate IM CN subsystem entities to remote UE)
11. SIP 200 (OK) response (remote UE to intermediate IM CN subsystem entities) – see example in table A.14.4-11
The remote US sends a SIP 200 (OK) with an SDP offer containing Media A and Media B information.
Table A.7.4-11: SIP 200 (OK) (remote UE to intermediate IM CN subsystem entities)
SIP/2.0 200 OK
Via:
To:
Call-ID:
Cseq: 127 INVITE
Supported: 100rel; precondition
Contact: <sip: user3_public3@home3.net>; gr=urn:uuid:f81d4fae-7dec-11d0-a765-00a0c67t6br4>
Allow:
Accept: application/sdp;
Content-Type: application/sdp
Content-Length: (…)
v=0
o=- 2987933300 2987933300 IN IP6 5555::aaa:bbb::ccc:ddd
s=-
c=IN IP6 5555::aaa:bbb::ccc:ddd
t=0 0
m=audio 4444 RTP/AVP 97
a=rtpmap:97 PCMU/8000
m=video 0 RTP/AVP 98
a=rtpmap:98 MPV/9000
12. SIP 200 (OK) response (intermediate IM CN subsystem entities to SCC AS)
13-14. SIP 200 (OK) response (SCC AS to UE-2 through IM CN subsystem entities)
The SCC AS sends a 200 (OK) response.
15-16. SIP ACK request (controllee UE to SCC AS)
17-18. SIP ACK request (SCC AS to remote UE)