11.1.9 MO MMTEL voice call setup from NR RRC_IDLE / EPS Fallback with redirection / Single registration mode with N26 interface / voiceFallbackIndication
38.523-13GPP5GSPart 1: ProtocolRelease 17TSUser Equipment (UE) conformance specification
11.1.9.1 Test Purpose (TP)
(1)
with { UE being in NR RRC_CONNECTED state after having requested an MMTEL call establishment and the MO IMS voice session establishment has been initiated }
ensure that {
when { UE receives an RRCRelease message which includes redirectedCarrierInfo indicating redirection to E-UTRA and with voiceFallbackIndication }
then {UE selects the E-UTRA cell, uses “mo-VoiceCall” as the establishment cause value in RRC Connection Request, performs a TAU procedure, and, successfully completes the MMTEL call setup in EPS }
}
11.1.9.2 Conformance requirements
References: The conformance requirements covered in the current TC are specified in: TS 24.501, clauses 4.5.4.1; TS 38.331, clause 5.3.8.3, 5.3.11. Unless otherwise stated these are Rel-16 requirements.
[TS 24.501, clause 4.5.4.1]
When the UE is in 5GMM-IDLE mode or 5GMM-IDLE mode with suspend indication, upon receiving a request from the upper layers for an access attempt, the NAS shall categorize the access attempt into access identities and an access category following:
a) subclause 4.5.2, table 4.5.2.1 and table 4.5.2.2, and subclause 4.5.3, if the UE is not operating in SNPN access mode; or
b) subclause 4.5.2A, table 4.5.2A.1 and table 4.5.2A.2, and subclause 4.5.3, if the UE is operating in SNPN access mode,
and provide the applicable access identities and the access category to the lower layers for the purpose of access control checking. In this request to the lower layer the NAS can also provide to the lower layer the RRC establishment cause determined as specified in subclause 4.5.6 of this specification.
NOTE 1: The access barring check is performed by the lower layers.
NOTE 2: As an implementation option, the NAS can provide the RRC establishment cause to the lower layers after being informed by the lower layers that the access attempt is allowed.
If the UE has uplink user data pending for one or more PDU sessions when it builds a REGISTRATION REQUEST or SERVICE REQUEST message as initial NAS message, the UE shall indicate the respective PDU sessions in the Uplink data status IE as specified in subclause 5.5.1.3.2 and 5.6.1.2.1, regardless of the access category for which the access barring check is performed.
If the UE is registered for 5GS services with control plane CIoT 5GS optimization has uplink user data pending for one or more PDU sessions when it builds a CONTROL PLANE SERVICE REQUEST message as initial NAS message, the UE shall indicate the respective PDU sessions as specified in subclause 5.6.1.2.2, regardless of the access category for which the access barring check is performed.
NOTE 3: The UE indicates pending user data for all the respective PDU sessions, even if barring timers are running for some of the corresponding access categories.
If the lower layers indicate that the access attempt is allowed, the NAS shall initiate the procedure to send the initial NAS message for the access attempt.
[TS 38.331, clause 5.3.8.3]
The UE shall:
1> delay the following actions defined in this sub-clause 60 ms from the moment the RRCRelease message was received or optionally when lower layers indicate that the receipt of the RRCRelease message has been successfully acknowledged, whichever is earlier;
1> stop timer T380, if running;
1> stop timer T320, if running;
1> if timer T316 is running;
2> stop timer T316;
2> clear the information included in VarRLF-Report, if any;
1> stop timer T350, if running;
1> if the AS security is not activated:
2> ignore any field included in RRCRelease message except waitTime;
2> perform the actions upon going to RRC_IDLE as specified in 5.3.11 with the release cause ‘other’ upon which the procedure ends;
1> if the RRCRelease message includes redirectedCarrierInfo indicating redirection to eutra:
2> if cnType is included:
3> after the cell selection, indicate the available CN Type(s) and the received cnType to upper layers;
NOTE 1: Handling the case if the E-UTRA cell selected after the redirection does not support the core network type specified by the cnType, is up to UE implementation.
2> if voiceFallbackIndication is included:
3> consider the RRC connection release was for EPS fallback for IMS voice (see TS 23.502 [43]);
[TS 38.331, clause 5.3.11]
UE shall:
1> reset MAC;
1> if T302 is running:
2> stop timer T302;
2> perform the actions as specified in 5.3.14.4;
1> stop all timers that are running except T320 and T325;
1> discard the UE Inactive AS context;
1> set the variable pendingRnaUpdate to false, if that is set to true;
1> discard the KgNB, the KRRCenc key, the KRRCint, the KUPint key and the KUPenc key, if any;
1> release all radio resources, including release of the RLC entity, the MAC configuration and the associated PDCP entity and SDAP for all established RBs;
1> indicate the release of the RRC connection to upper layers together with the release cause;
1> enter RRC_IDLE and perform cell selection as specified in TS 38.304 [20], except if going to RRC_IDLE was triggered by selecting an inter-RAT cell while T311 was running;
1> if going to RRC_IDLE was triggered by reception of the RRCRelease message including a waitTime:
2> start timer T302 with the value set to the waitTime;
2> inform the upper layer that access barring is applicable for all access categories except categories ‘0’ and ‘2’.
11.1.9.3 Test description
11.1.9.3.1 Pre-test conditions
System Simulator:
– 2 cells
– NR Cell 1 is configured according to TS 38.508-1 [4] Table 4.4.2-3 and is connected to 5GC.
– E-UTRA Cell 1 is configured to TS 36.508 [7] Table 4.4.2-2 and is connected to EPC.
– System information for the NR Cell 1 in accordance with combination NR-6 in TS 38.508-1 [4] sub-clause 4.4.3.1.2, and, for the E-UTRA Cell 1 in accordance with system information combination 31 as defined in TS 36.508 [7], subclause 4.4.3.1.1.
– Power levels are constant and as defined in Tables 11.1.9.3.1-1/2.
Table 11.1.9.3.1-1: Time instances of cell power level and parameter changes for conducted test environment
|
Parameter name |
Unit |
NR Cell 1 |
E-UTRA Cell 1 |
Remark |
|
|
T0 |
SS/PBCH SSS EPRE |
dBm/SCS |
-88 |
||
|
RS EPRE |
dBm/15kHz |
-85 |
Table 11.1.9.3.1-2: Time instances of cell power level and parameter changes for OTA test environment
|
Parameter name |
Unit |
NR Cell 1 |
E-UTRA Cell 1 |
Remark |
|
|
T0 |
SS/PBCH SSS EPRE |
dBm/SCS |
-82 |
– |
|
|
RS EPRE |
dBm/15kHz |
– |
-85 |
UE:
– The UE is configured to use IMS preconditions
Preamble:
With E-UTRA Cell 1 "Serving cell" and NR Cell 1 "Non-suitable "Off" cell" in accordance with TS 38.508-1 [4], Table 6.2.2.1-3, the UE is brought to state RRC_IDLE using generic procedure parameters Connectivity (E-UTRA/EPC) and Unrestricted nr PDN (On) in accordance with the procedure described in TS 38.508-1 [4], clause 4.5.2. 4G GUTI and eKSI are assigned and security context established
The UE is switched-off
With E-UTRA Cell 1 "Non-suitable "Off" cell" and NR Cell 1 "Serving cell" in accordance with TS 38.508-1 [4], Table 6.2.2.1-3, the UE is brought to state 1N-A, RRC_IDLE Connectivity (NR), in accordance with the procedure described in TS 38.508-1 [4], Table 4.5.2.2-2. 5G-GUTI and ngKSI are assigned and security context established.
11.1.9.3.2 Test procedure sequence
Table 11.1.9.3.2-1: Main behaviour
|
St |
Procedure |
Message Sequence |
TP |
Verdict |
|
|
U – S |
Message |
||||
|
0 |
Void |
– |
– |
– |
– |
|
1 |
Make the UE attempt an MTSI MO Speech Call (Note 1). |
– |
– |
– |
– |
|
2 |
UE sends NR RRCSetupRequest with EstablishmentCause set to ‘mo-VoiceCall’. |
–> |
NR RRC: RRCSetupRequest |
– |
– |
|
3 |
SS transmits an NR RRCSetup message |
<– |
NR RRC: RRCSetup |
– |
– |
|
4 |
UE transmits an NR RRCSetupComplete message to confirm the successful completion of the connection establishment including initiation of 5GSM procedure by including the SERVICE REQUEST message with Service Type set to ‘data’. |
–> |
NR RRC: RRCSetupComplete 5GSM: SERVICE REQUEST |
– |
– |
|
5 |
Set the power levels according to “T0” as per Table 11.1.9.3.1-1/2. |
– |
– |
– |
– |
|
6-7 |
Void |
– |
– |
– |
– |
|
8 |
Steps 5-8 of expected sequence from Table 4.5.4.2-3 as defined in TS 38.508-1 [4] are performed. |
– |
– |
– |
– |
|
9-13 |
Steps 1-5 of expected sequence from A.9.1 as defined in TS 34.229-5 [41] are performed for setting up MTSI MO speech call – EPS fallback. |
– |
– |
– |
– |
|
14 |
SS transmits RRCRelease message indicating redirection to E-UTRA Cell 1. |
<– |
NR RRC: RRCRelease |
– |
– |
|
– |
EXCEPTION: Unless otherwise stated all the messages below are transmitted on the cell specified in the test case. |
– |
– |
– |
– |
|
15 |
The UE transmits an RRCConnectionRequest message on the cell specified in the test case. |
–> |
RRC: RRCConnectionRequest |
1 |
P |
|
16-20 |
UE performs generic procedure as defined in TS 38.508-1 [4], Table 4.9.7.2.2-1 Steps 2-6 for N1 to S1 Inter mode change with condition ‘connected without release’ & ‘mapped 5G security context’. |
– |
– |
– |
– |
|
21-24 |
Generic Test Procedure as defined in Steps 5-8 of TS 36.508-1 [4] Table 4.5A.6.3-1 is performed to establish radio bearer corresponding to IMS PDN. |
– |
– |
– |
– |
|
– |
EXCEPTION: Steps 25a1-25a2 describe a step sequence depending on UE implementation. |
– |
– |
– |
– |
|
25a1-25a2 |
The UE may perform steps 1-2 according to TS 34.229-1 subclause C.46 to perform IMS re-registration on EUTRAN. |
– |
– |
– |
– |
|
26 |
The SS configures a new RLC-UM data radio bearer with condition DRB (0,1), associated with the dedicated EPS bearer context. RRCConnectionReconfiguration message contains the ACTIVATE DEDICATED EPS BEARER CONTEXT REQUEST message. EPS bearer context #4 (QCI 1) according to table 6.6.2-1: Reference dedicated EPS bearer contexts. |
<– |
RRC: RRCConnectionReconfiguration NAS: ACTIVATE DEDICATED EPS BEARER CONTEXT REQUEST |
– |
– |
|
– |
EXCEPTION: In parallel to the events described in steps 27-28 the steps specified in table 11.1.9.3.2-2 will take place. |
– |
– |
– |
– |
|
27 |
The UE transmits an RRCConnectionReconfigurationComplete message to confirm the establishment of the new data radio bearer, associated with the dedicated EPS bearer. |
–> |
RRC: RRCConnectionReconfigurationComplete |
– |
– |
|
28 |
The UE transmits an ACTIVATE DEDICATED EPS BEARER CONTEXT ACCEPT message. |
–> |
RRC: ULInformationTransfer NAS:ACTIVATE DEDICATED EPS BEARER CONTEXT ACCEPT |
1 |
P |
|
29 |
UE is triggered by MMI to release the call. |
– |
– |
– |
– |
|
30-33 |
Follow the Test Steps 2-5 as defined in TS 34.229-1 [35] subclause C.32 for Generic test procedure for MO release of IMS call followed by EPS Bearer Deactivation. |
– |
– |
– |
– |
Table 11.1.9.3.2-2: Parallel behaviour
|
St |
Procedure |
Message Sequence |
TP |
Verdict |
|
|
U – S |
Message |
||||
|
1-4A |
Steps 1 to 5 of the the generic procedure “EPS Fallback for Voice Call / steps after fallback / 5GS” as defined in Appendix A.9.2 of TS 34.229-5 [41] take place. |
– |
– |
– |
– |
|
5 |
Check: Does the UE perform step 6 of the generic procedure “EPS Fallback for Voice Call / steps after fallback / 5GS” as defined in Appendix A.9.2 of TS 34.229-5 [41] take place? |
–> |
SIP: ACK |
1 |
P |
11.1.9.3.3 Specific message contents
Table 11.1.9.3.3-1: RRCRelease (step 6, table 11.1.9.3.2-1)
|
Derivation path: TS 38.508-1 [4] Table Table 4.6.1-16 |
|||
|
Information Element |
Value/Remark |
Comment |
Condition |
|
RRCRelease ::= SEQUENCE { |
|||
|
criticalExtensions CHOICE { |
|||
|
rrcRelease SEQUENCE { |
|||
|
redirectedCarrierInfo CHOICE { |
|||
|
eutra SEQUENCE { |
|||
|
eutraFrequency |
Downlink EARFCN of cell 1 |
||
|
cnType |
epc |
||
|
} |
|||
|
} |
|||
|
} |
|||
|
nonCriticalExtension { |
|||
|
nonCriticalExtension { |
|||
|
voiceFallbackIndication-r16 |
true |
||
|
} |
|||
|
} |
|||
|
} |
|||
|
} |
|||
Table 11.1.9.3.3-2: RRCConnectionRequest (step 15, table 11.1.9.3.2-1)
|
Derivation path: TS 36.508-1 Table Table 4.6.1-16 |
|||
|
Information Element |
Value/Remark |
Comment |
Condition |
|
RRCConnectionRequest ::= SEQUENCE { |
|||
|
criticalExtensions CHOICE { |
|||
|
rrcConnectionRequest-r8 SEQUENCE { |
|||
|
ue-Identity CHOICE { |
|||
|
s-TMSI |
Any allowed value |
||
|
} |
|||
|
establishmentCause |
mo-VoiceCall-v1280 |
mo-VoiceCall |
|
|
spare |
Present but contents not checked |
||
|
} |
|||
|
} |
|||
|
} |
|||
Table 11.1.9.3.3-3: SystemInformationBlockType2 for E-UTRA Cell 1 (preamble and all steps, Table 11.1.9.3.2-1)
|
Derivation Path: 36.508, Table 4.4.3.3-1 |
|||
|
Information Element |
Value/remark |
Comment |
Condition |
|
SystemInformationBlockType2 ::= SEQUENCE { |
|||
|
voiceServiceCauseIndication-r12 |
true |
||
|
} |
|||