8.33 Inviting user to conference by sending a REFER request to the conference focus / Video / 5GS

34.229-53GPPInternet Protocol (IP) multimedia call control protocol based on Session Initiation Protocol (SIP) and Session Description Protocol (SDP)Part 5: Protocol conformance specification using 5G System (5GS)Release 16TSUser Equipment (UE) conformance specification

8.33.1 Test Purpose (TP)

(1)

with { UE being registered to IMS }

ensure that {

when { UE is made to start a video conference call }

then { UE sends INVITE to the conference factory and completes the conference call initiation and subscribes to conference event }

}

(2)

with { Video Conference call going on }

ensure that {

when { UE is made to invite another user to the conference call }

then { UE sends REFER to the conference focus }

}

(3)

with { UE having invited another user to the Video conference call }

ensure that {

when { UE receives 202 Accepted followed by notification messages for the REFER request, the confirmation on the other user and conditional conference event package }

then { UE sends 200 OK for each received NOTIFY request }

}

(4)

with {Video Conference call going on }

ensure that {

when { UE is made to leave the call }

then { UE sends BYE and processes notification for conf event if any }

}

8.33.2 Conformance Requirements

The conformance requirements covered in the present test case are, unless otherwise stated, Rel-15 requirements.

[TS 24.147, clause 5.3.1.5.3]:

Upon generating a REFER request in accordance with the procedures specified in 3GPP TS 24.229 [5], IETF RFC 3515 [17] as updated by IETF RFC 6665 [10] and IETF RFC 7647 [39] that is destined to the conference focus in order to invite another user to a specific conference, the conference participant shall:

1) set the request URI of the REFER request to the conference URI to which the user is invited to;

2) set the Refer-To header of the REFER request to the SIP URI or tel URL of the user who is invited to the conference;

3) either include the "method" URI parameter with the value "INVITE" or omit the "method" URI parameter in the Refer-To header; and

NOTE: Other headers of the REFER request will be set in accordance with 3GPP TS 24.229 [5].

4) send the REFER request towards the conference focus that is hosting the conference.

The UE may additionally include the Referred-By header to the REFER request and set it to the URI of the conference participant that is sending the REFER request.

In case of an active session the UE may additionally include the Replaces header in the header portion of the SIP URI of the Refer-to header field of the REFER request. If the user involved in the active session is identified by a tel URI, the UE shall convert the tel URI to an SIP URI as described in RFC 3261 [7] before including the Replaces header field. The included Replaces header field shall refer to the active dialog that is replaced by the ad-hoc conference. The Replaces header field shall comply with RFC 3891 [33].

Afterwards the UE shall treat incoming NOTIFY requests that are related to the previously sent REFER request in accordance with RFC 3515 [17] as updated by RFC 6665 [10] and may indicate the received information to the user.

8.33.3 Test description

8.33.3.1 Pre-test conditions

System Simulator:

– 1 NR Cell connected to 5GC, default parameters.

– SS has performed AKAv1-MD5 authentication with the UE and accepted the registration.

UE:

– UE contains either ISIM and USIM applications or only USIM application on UICC.

– UE is configured to register for IMS after switch on.

Preamble:

– The UE is in test state 1N-A (TS 38.508-1 [21]) and registered to IMS.

8.33.3.2 Test procedure sequence

Table 8.33.3.2-1: Main Behaviour

St	Procedure	Message Sequence		TP	Verdict
		U – S	Message
1	The UE is made to attempt an IMS Conference call	–	–	–	–
2	The UE sends INVITE with the first SDP offer. (Step 1 in annex A.25 )	–>	INVITE	1	P
3-14	Steps 2-13 of annex A.25 happen.	–	–	–	–
15	The UE is made to invite another user to the conference	–	–	–	–
16	The UE sends REFER to SS referring to the conference (Step 1 in annex A.26 )	–>	REFER	2	P
17	The SS responds with a 202 final response (Step 2 in annex A.26 )	<–	202 Accepted	–	–
18	The SS sends initial NOTIFY for the implicit subscription created by the REFER request (Step 3 in annex A.26 )	<–	NOTIFY	–	–
19	The UE responds the NOTIFY with 200 OK (Step 4 in annex A.26 )	–>	200 OK	3	P
20	The SS sends a NOTIFY related to REFER request to confirm that the invited user was able to join the conference (Step 5 in annex A.26 )	<–	NOTIFY	–	–
21	The UE responds the NOTIFY with 200 OK (Step 6 in annex A.26 )	–>	200 OK	3	P
22	Optional: If the UE has subscribed the conference event package, the SS sends a NOTIFY for conference event package to inform that the invited user was able to join the conference. (Step 7 in annex A.26 )	<–	NOTIFY	–	–
23	Optional: The UE responds the NOTIFY with 200 OK (Step 8 in annex A.26 )	–>	200 OK	3	P
24	The UE is made to leave the conference	–	–	–	–
25	The UE sends BYE to ler leaving the conference (Step 1 in annex A.27 )	–>	BYE	4	P
26	The SS sends 200 OK for BYE (Step 2 in annex A.27 )	<–	200 OK	–	–
27	If the UE had subscribed to the conference event package, the SS notifies the UE that its subscription to conference event package is terminated (Step 3 in annex A.27 )	–>	NOTIFY	–	–
28	The UE sends 200 OK for NOTIFY (if sent by SS) (Step 4 in annex A.27 )	–>	200 OK	–	–

8.33.3.3 Specific message contents

None as fully described in Annex A.25, A.26 and A.27.