7.2 MTSI MO Voice Call / 504 Server Time-out / 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

7.2.1 Test Purpose (TP)

(1)

with { UE being registered to IMS and UE having sent an INVITE request }

ensure that {

when { UE receives 504 Server Time-out response }

then { UE performs initial registration to IMS }

}

7.2.2 Conformance Requirements

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

[TS 24.229, clause 5.1.2A.1.6]

In the event the UE receives a 504 (Server Time-out) response containing:

1) a P-Asserted-Identity header field set to a value equal to a URI:

a) from the Service-Route header field value received during registration; or

b) from the Path header field value received during registration; and

NOTE 1: If there are multiple registration flows associated with the registration, then the UE has received from the P-CSCF during registration multiple sets of Path header field and Service-Route header field values. The Path header field value and Service-Route header field value corresponding to the flow on which the 504 (Server Time-out) response was received are checked.

2) a Content-Type header field set according to subclause 7.6 (i.e. "application/3gpp-ims+xml"), independent of the value or presence of the Content-Disposition header field, independent of the value or presence of Content-Disposition parameters,

then the following treatment is applied:

a) if the 504 (Server Time-out) response includes an IM CN subsystem XML body as described in subclause 7.6 with the <ims-3gpp> element, including a version attribute, with the <alternative-service> child element:

A) with the <type> child element set to "restoration" (see table 7.6.2); and

B) with the <action> child element set to "initial-registration" (see table 7.6.3);

then the UE:

– shall initiate S-CSCF restoration procedures by performing an initial registration as specified in subclause 5.1.1.2; and

– may provide an indication to the user based on the text string contained in the <reason> child element of the <alternative-service> child element of the <ims-3gpp> element.

NOTE 2: If the UE has discovered multiple P-CSCF addresses and has information that the P-CSCF was unable to forward the request resulting in sending back the 504 (Server Time-out) response, when starting the initial registration it is appropriate for the UE to select a P-CSCF address different from the one used for the registration binding on which the 504 (Server Time-out) response was received.

7.2.3 Test description

7.2.3.1 Pre-test conditions

System Simulator:

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

UE:

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

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

– The UE is either configured to use preconditions or to not use preconditions or does not support preconditions.

Preamble:

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

7.2.3.2 Test procedure sequence

Table 7.2.3.2-1: Main Behaviour

St	Procedure	Message Sequence		TP	Verdict
		U – S	Message
1	UE is made to attempt an IMS voice call.	–	–	–	–
2-7	Steps 2-7 of generic procedure specified in Table 4.9.15.2.2-1 of TS 38.508-1 [21] are performed.	–	–	–	–
–	EXCEPTION: In parallel to INVITE at Steps 8 a or 8b, step described in Table 7.2.3.2-2: Parallel behaviour takes place.	–>	–	–	–
–	EXCEPTION: Steps 8a to 8b describe behaviour that depends on UE configuration; the “lower case letter” identifies a step sequence that takes place if such configuration was conducted.	–	–	–	–
8a	IF the UE is configured to use preconditions THEN step 1 of Annex A.4.1 takes place.	–>	INVITE	–	–
8b	ELSE step 1 of Annex A.4.2 takes place.	–>	INVITE	–	–
9	SS sends 504 Server Time-out	<–	504 Server Time-out	–	–
9A	UE acknowledges the reception of 504 Server Time-out.	–>	ACK	–	–
10	Check: Does the UE send an initial registration request?	–>	REGISTER	1	P
11-17	Continue with Annex A.2 steps 2-8 in order to get the UE in a stable registered state.	–	–	–	–

Table 7.2.3.2-2: Parallel behaviour

St	Procedure	Message Sequence		TP	Verdict
		U – S	Message
1	The UE transmits an RRCReconfigurationComplete message.	–>	NR RRC: RRCReconfigurationComplete	–	–

Table 7.2.3.3-3: ACK (step 9A, Table 7.2.3.2-1)

Derivation path: TS 34.229-1 [2], Table in subclause A.2.7 Conditions A1 and A4

7.2.3.3 Specific message contents

Table 7.2.3.3-1: 504 Server Time-out (step 3, Table 7.2.3.2-1)

Derivation path: TS 34.229-1 [2], Table in subclause A.4.6

Table 7.2.3.3-2: REGISTER (step 4, Table 7.2.3.2-1)

Derivation path: TS 34.229-1 [2], Table in subclause A.1.1 conditions A1 and A32

7.3 Void