9.1.12 NSAC / Mobility management aspects
38.523-13GPP5GSPart 1: ProtocolRelease 17TSUser Equipment (UE) conformance specification
9.1.12.1 NSAC / Initial registration / Back-off timer
9.1.12.1.1 Test Purpose (TP)
(1)
with { UE in UE in 5GMM-DEREGISTERED state }
ensure that {
when { UE is switched on }
then { UE transmits REGISTRATION REQUEST message with ER-NSSAI bit set to "Extended rejected NSSAI supported" in the 5GMM capability IE }
}
(2)
with { UE in 5GMM-REGISTERED-INITIATED state }
ensure that {
when { UE receives the rejected NSSAI in the REGISTRATION ACCEPT message with the rejection cause of "S-NSSAI not available due to maximum number of UEs reached" and the back-off timer value received along with the S-NSSAI is not zero }
then { UE shall stores the rejected NSSAI and start the timer T3526 }
}
(3)
with { UE in 5GMM-REGISTERED state and UE stores one or more S-NSSAIs in the rejected NSSAI with the rejection cause "S-NSSAI not available due to maximum number of UEs reached" }
ensure that {
when { The timer T3526 associated with the S-NSSAI expires }
then { UE remove the S-NSSAI from the rejected NSSAI for the maximum number of UEs reached }
}
(4)
with { UE in 5GMM-REGISTERED state and UE stores one or more S-NSSAIs in the rejected NSSAI with the rejection cause "S-NSSAI not available due to maximum number of UEs reached" }
ensure that {
when { UE is switched off }
then { UE remove the S-NSSAI from the rejected NSSAI for the maximum number of UEs reached }
}
9.1.12.1.2 Conformance requirements
References: The conformance requirements covered in the current TC are specified in: TS 24.501 clauses 5.5.1.2.2, 5.5.1.2.4 and 10.2. Unless otherwise stated these are Rel-17 requirements.
[TS 24.501 clause 5.5.1.2.2]
The UE initiates the registration procedure for initial registration by sending a REGISTRATION REQUEST message to the AMF, starting timer T3510. If timer T3502 is currently running, the UE shall stop timer T3502. If timer T3511 is currently running, the UE shall stop timer T3511.
…
The UE shall set the ER-NSSAI bit to "Extended rejected NSSAI supported" in the 5GMM capability IE of the REGISTRATION REQUEST message.
[TS 24.501 clause 5.5.1.2.4]
If the UE supports extended rejected NSSAI and the AMF determines that maximum number of UEs reached for one or more S-NSSAI(s) in the requested NSSAI as specified in subclause 4.6.2.5, the AMF shall include the rejected NSSAI containing one or more S-NSSAIs with the rejection cause "S-NSSAI not available due to maximum number of UEs reached" in the Extended rejected NSSAI IE in the REGISTRATION ACCEPT message. In addition, the AMF may include a back-off timer value for each S-NSSAI with the rejection cause "S-NSSAI not available due to maximum number of UEs reached" included in the Extended rejected NSSAI IE of the REGISTRATION ACCEPT message. To avoid that large numbers of UEs simultaneously initiate deferred requests, the network should select the value for the backoff timer for each S-NSSAI for the informed UEs so that timeouts are not synchronised.
…
The UE receiving the rejected NSSAI in the REGISTRATION ACCEPT message takes the following actions based on the rejection cause in the rejected S-NSSAI(s):
"S-NSSAI not available in the current PLMN or SNPN"
The UE shall add the rejected S-NSSAI(s) in the rejected NSSAI for the current PLMN or SNPN as specified in subclause 4.6.2.2 and shall not attempt to use this S-NSSAI(s) in the current PLMN or SNPN until switching off the UE, the UICC containing the USIM is removed, the entry of the "list of subscriber data" with the SNPN identity of the current SNPN is updated, or the rejected S-NSSAI(s) are removed or deleted as described in subclause 4.6.2.2.
"S-NSSAI not available in the current registration area"
The UE shall add the rejected S-NSSAI(s) in the rejected NSSAI for the current registration area as specified in subclause 4.6.2.2 and shall not attempt to use this S-NSSAI(s) in the current registration area until switching off the UE, the UE moving out of the current registration area, the UICC containing the USIM is removed, the entry of the "list of subscriber data" with the SNPN identity of the current SNPN is updated, or the rejected S-NSSAI(s) are removed or deleted as described in subclause 4.6.2.2.
"S-NSSAI not available due to the failed or revoked network slice-specific authentication and authorization"
The UE shall store the rejected S-NSSAI(s) in the rejected NSSAI for the failed or revoked NSSAA as specified in subclause 4.6.2.2 and shall not attempt to use this S-NSSAI in the current PLMN or SNPN over any access until switching off the UE, the UICC containing the USIM is removed, the entry of the "list of subscriber data" with the SNPN identity of the current SNPN is updated, or the rejected S-NSSAI(s) are removed or deleted as described in subclause 4.6.1 and 4.6.2.2.
"S-NSSAI not available due to maximum number of UEs reached"
Unless the back-off timer value received along with the S-NSSAI is zero, the UE shall add the rejected S-NSSAI(s) in the rejected NSSAI for the maximum number of UEs reached as specified in subclause 4.6.2.2 and shall not attempt to use this S-NSSAI in the current PLMN or SNPN over the current access until switching off the UE, the UICC containing the USIM is removed, the entry of the "list of subscriber data" with the SNPN identity of the current SNPN is updated, or the rejected S-NSSAI(s) are removed as described in subclause 4.6.2.2.
NOTE 15: If the back-off timer value received along with the S-NSSAI in the rejected NSSAI for the maximum number of UEs reached is zero as specified in subclause 10.5.7.4a of TS 24.008, the UE does not consider the S-NSSAI as the rejected S-NSSAI.
If there is one or more S-NSSAIs in the rejected NSSAI with the rejection cause "S-NSSAI not available due to maximum number of UEs reached", then for each S-NSSAI, the UE shall behave as follows:
a) stop the timer T3526 associated with the S-NSSAI, if running;
b) start the timer T3526 with:
1) the back-off timer value received along with the S-NSSAI, if a back-off timer value is received along with the S-NSSAI that is neither zero nor deactivated; or
2) an implementation specific back-off timer value, if no back-off timer value is received along with the S-NSSAI; and
c) remove the S-NSSAI from the rejected NSSAI for the maximum number of UEs reached when the timer T3526 associated with the S-NSSAI expires.
[TS 24.501, clause 10.2]
Table 10.2.1: Timers of 5GS mobility management – UE side
|
TIMER NUM. |
TIMER VALUE |
STATE |
CAUSE OF START |
NORMAL STOP |
ON |
|---|---|---|---|---|---|
|
T3526 |
NOTE 9 |
5GMM-DEREGISTERED 5GMM-REGISTERED |
Rejected S-NSSAI with rejection cause "maximum number of UEs per network slice reached" received. |
The associated rejected S-NSSAI for the maximum number of UEs reached as specified in subclause 4.6.2.2 deleted. |
Remove the S-NSSAI in the rejected NSSAI for the maximum number of UEs reached associated with the T3526 timer. |
|
… NOTE 9: The value of this timer is provided by the network operator during the registration procedure or the generic UE configuration update procedure along with the rejected S-NSSAI with rejection cause "maximum number of UEs per network slice reached". The default value of this timer is implementation specific with a minimum value of 12 minutes and used if the network does not provide a value in the REGISTRATION ACCEPT message, the REGISTRATION REJECT message, or the CONFIGURATION UPDATE COMMAND message along with the rejected S-NSSAI with rejection cause "maximum number of UEs per network slice reached". … |
|||||
9.1.12.1.3 Test description
9.1.12.1.3.1 Pre-test conditions
System Simulator:
– NGC Cell A belongs to Home PLMN and TAI1 and set as serving cell;
UE:
– UE is previously registered on NGC Cell A using default message contents according to TS 38.508-1 [4];
Preamble:
The UE is in state Switched OFF (state 0N-B) according to TS 38.508-1 [4].
9.1.12.1.3.2 Test procedure sequence
Table 9.1.12.1.3.2-1: Main behaviour
|
St |
Procedure |
Message Sequence |
TP |
Verdict |
|
|
U – S |
Message |
||||
|
1 |
The UE is switched on. |
– |
– |
– |
– |
|
2 |
Check: Does UE transmit a REGISTRATION REQUEST message including ER-NSSAI bit? |
–> |
REGISTRATION REQUEST |
1 |
P |
|
3-11 |
Steps 5 to 13 of the generic procedure for NR RRC_IDLE specified in TS 38.508-1 subclause 4.5.2 are performed. |
– |
– |
– |
– |
|
12 |
The SS transmits a REGISTRATION ACCEPT message including S-NSSAI=1 in extended rejected NSSAI with back-off timer set to 60 seconds and S-NSSAI=2 in extended rejected NSSAI with back-off timer set to 1 hour Note: Now UE should start timer T3526 associated with S-NSSAI=1 and T3526 associated with S-NSSAI=2. |
<– |
REGISTRATION ACCEPT |
– |
– |
|
13 |
The UE transmits an ULInformationTransfer message and a REGISTRATION COMPLETE message. |
–> |
REGISTRATION COMPLETE |
– |
– |
|
EXCEPTION: Step 14a1 is performed if pc_noOf_PDUsSameConnection > 0. |
|||||
|
14a1 |
The generic procedure for UE-requested PDU session establishment, specified in subclause 4.5A.2, takes place performing establishment of UE-requested PDU session(s) with ExpectedNumberOfNewPDUSessions = pc_noOf_PDUsSameConnection. |
– |
– |
– |
– |
|
15 |
SS releases the RRC connection |
– |
– |
– |
– |
|
16 |
Check: Are S-NSSAI=1 and S-NSSAI=2 in the Rejected NSSAI list with cause ‘S-NSSAI not available due to maximum number of UEs reached’’ associated with current PLMN using AT/MMI command (+C5GNSSAIRDP)? |
– |
– |
2 |
P |
|
17 |
Cause the UE to request establishment of PDU session with S-NSSAI=1.(Note 1) |
– |
– |
– |
– |
|
18 |
Check: Does the UE transmit an RRCSetupRequest message within T3526 associated with S-NSSAI=1 in the next 15 seconds? |
–> |
NR RRC: RRCSetupRequest |
2 |
F |
|
19 |
Cause the UE to request establishment of PDU session with S-NSSAI=2.(Note 1) |
– |
– |
– |
– |
|
20 |
Check: Does the UE transmit an RRCSetupRequest message within T3526 associated with S-NSSAI=2 in the next 15 seconds? |
–> |
NR RRC: RRCSetupRequest |
2 |
F |
|
21 |
Wait for the expiry of T3526 associated with S-NSSAI=1. |
– |
– |
– |
– |
|
22 |
Check: Using AT/MMI command (+C5GNSSAIRDP) verify that S-NSSAI=1 is not in the Rejected NSSAI list associated with current PLMN |
– |
– |
3 |
P |
|
23 |
Switch off procedure in RRC_IDLE specified in TS 38.508-1 subclause 4.9.6.1 is performed. |
– |
– |
– |
– |
|
24 |
The SS configures NGC Cell A as the "Non-suitable cell" |
– |
– |
– |
– |
|
25 |
The UE is switched on.(Note2) |
– |
– |
– |
– |
|
26 |
Check: Using AT/MMI command (+C5GNSSAIRDP) verify that S-NSSAI=2 is not in the Rejected NSSAI list associated with current PLMN |
4 |
P |
||
|
27 |
The SS configures NGC Cell A as the "Serving cell". |
– |
– |
– |
– |
|
28-46 |
Steps 2 to 20a1 of the generic procedure for NR RRC_IDLE specified in TS 38.508-1 subclause 4.5.2 are performed. |
– |
– |
– |
– |
|
Note1: The request to establish a PDU session may be performed by MMI or AT Command. Note2: UE is switched on before the expiry of T3526 associated with S-NSSAI=2 |
|||||
9.1.12.1.3.3 Specific message contents
Table 9.1.12.1.3.3-1: REGISTRATION REQUEST (step 2, Table 9.1.12.1.3.2-1)
|
Derivation path: TS 38.508-1 Table 4.7.1-6 |
||||
|
Information Element |
Value/remark |
Comment |
Condition |
|
|
5GS registration type value |
‘001’B |
Initial registration |
||
|
5GMM capability |
||||
|
ER-NSSAI |
‘1’B |
Extended rejected NSSAI supported |
||
Table 9.1.12.1.3.3-2: REGISTRATION ACCEPT (step 12, Table 9.1.12.1.3.2-1)
|
Derivation path: TS 38.508-1 Table 4.7.1-7 |
||||
|
Information Element |
Value/remark |
Comment |
Condition |
|
|
5GS registration result |
||||
|
5GS registration result value |
‘001’B |
3GPP access |
||
|
Allowed NSSAI |
||||
|
S-NSSAI IEI |
S-NSSAI value 3 |
|||
|
Length of S-NSSAI contents |
‘00000001’B |
SST |
||
|
SST |
‘00000011’B |
SST value 3 |
||
|
SD |
Not Present |
|||
|
Mapped configured SST |
Not Present |
|||
|
Mapped configured SD |
Not Present |
|||
|
Configured NSSAI |
||||
|
S-NSSAI IEI |
S-NSSAI value 1 |
|||
|
Length of S-NSSAI contents |
‘00000001’B |
SST |
||
|
SST |
‘00000001’B |
SST value 1 |
||
|
SD |
Not Present |
|||
|
Mapped configured SST |
Not Present |
|||
|
Mapped configured SD |
Not Present |
|||
|
S-NSSAI IEI |
S-NSSAI value 2 |
|||
|
Length of S-NSSAI contents |
‘00000001’B |
SST |
||
|
SST |
‘00000010’B |
SST value 2 |
||
|
SD |
Not Present |
|||
|
Mapped configured SST |
Not Present |
|||
|
Mapped configured SD |
Not Present |
|||
|
Extended rejected NSSAI |
||||
|
Length of Extended rejected NSSAI contents |
2 entries |
|||
|
Partial extended rejected NSSAI list |
entry 1 |
|||
|
Type of list |
‘001’B |
S-NSSAIs with back-off timer |
||
|
Number of elements |
‘0000’B |
1 element |
||
|
Back-off timer value |
’10000010’B |
60 seconds |
||
|
Rejected S-NSSAI 1 |
S-NSSAI value 1 |
|||
|
Length of rejected S-NSSAI |
‘00000001’B |
SST |
||
|
Cause value |
‘0011’B |
S-NSSAI not available due to maximum number of UEs reached |
||
|
SST |
‘00000001’B |
SST value 1 |
||
|
SD |
Not Present |
|||
|
Mapped HPLMN SST |
Not present |
|||
|
Mapped HPLMN SD |
Not present |
|||
|
Partial extended rejected NSSAI list |
entry 2 |
|||
|
Type of list |
‘001’B |
S-NSSAIs with back-off timer |
||
|
Number of elements |
‘0000’B |
1 element |
||
|
Back-off timer value |
’00100001’B |
1 hour |
||
|
Rejected S-NSSAI 1 |
S-NSSAI value 2 |
|||
|
Length of rejected S-NSSAI |
‘00000001’B |
SST |
||
|
Cause value |
‘0011’B |
S-NSSAI not available due to maximum number of UEs reached |
||
|
SST |
‘00000010’B |
SST value 2 |
||
|
SD |
Not Present |
|||
|
Mapped HPLMN SST |
Not present |
|||
|
Mapped HPLMN SD |
Not present |
|||
9.1.12.2 NSAC / Initial registration / Back-off timer is not provided or zero
9.1.12.2.1 Test Purpose (TP)
(1)
with { UE in 5GMM-REGISTERED-INITIATED state }
ensure that {
when { UE receives the rejected NSSAI in the REGISTRATION ACCEPT message with the rejection cause of "S-NSSAI not available due to maximum number of UEs reached" and the back-off timer value is not provided }
then { UE shall start the timer T3526 with an implementation specific value with minimum 12 minuts }
}
(2)
with { UE in 5GMM-REGISTERED-INITIATED state }
ensure that {
when { UE receives the rejected NSSAI in the REGISTRATION ACCEPT message with the rejection cause of "S-NSSAI not available due to maximum number of UEs reached" and the back-off timer value the back-off timer value received along with the S-NSSAI is zero }
then { UE shall not consider the S-NSSAI as the rejected S-NSSAI }
}
9.1.12.1.2 Conformance requirements
References: The conformance requirements covered in the current TC are specified in: TS 24.501 clauses 5.5.1.2.4 and 10.2. Unless otherwise stated these are Rel-17 requirements.
[TS 24.501 clause 5.5.1.2.4]
If the UE supports extended rejected NSSAI and the AMF determines that maximum number of UEs reached for one or more S-NSSAI(s) in the requested NSSAI as specified in subclause 4.6.2.5, the AMF shall include the rejected NSSAI containing one or more S-NSSAIs with the rejection cause "S-NSSAI not available due to maximum number of UEs reached" in the Extended rejected NSSAI IE in the REGISTRATION ACCEPT message. In addition, the AMF may include a back-off timer value for each S-NSSAI with the rejection cause "S-NSSAI not available due to maximum number of UEs reached" included in the Extended rejected NSSAI IE of the REGISTRATION ACCEPT message. To avoid that large numbers of UEs simultaneously initiate deferred requests, the network should select the value for the backoff timer for each S-NSSAI for the informed UEs so that timeouts are not synchronised.
…
The UE receiving the rejected NSSAI in the REGISTRATION ACCEPT message takes the following actions based on the rejection cause in the rejected S-NSSAI(s):
"S-NSSAI not available in the current PLMN or SNPN"
The UE shall add the rejected S-NSSAI(s) in the rejected NSSAI for the current PLMN or SNPN as specified in subclause 4.6.2.2 and shall not attempt to use this S-NSSAI(s) in the current PLMN or SNPN until switching off the UE, the UICC containing the USIM is removed, the entry of the "list of subscriber data" with the SNPN identity of the current SNPN is updated, or the rejected S-NSSAI(s) are removed or deleted as described in subclause 4.6.2.2.
"S-NSSAI not available in the current registration area"
The UE shall add the rejected S-NSSAI(s) in the rejected NSSAI for the current registration area as specified in subclause 4.6.2.2 and shall not attempt to use this S-NSSAI(s) in the current registration area until switching off the UE, the UE moving out of the current registration area, the UICC containing the USIM is removed, the entry of the "list of subscriber data" with the SNPN identity of the current SNPN is updated, or the rejected S-NSSAI(s) are removed or deleted as described in subclause 4.6.2.2.
"S-NSSAI not available due to the failed or revoked network slice-specific authentication and authorization"
The UE shall store the rejected S-NSSAI(s) in the rejected NSSAI for the failed or revoked NSSAA as specified in subclause 4.6.2.2 and shall not attempt to use this S-NSSAI in the current PLMN or SNPN over any access until switching off the UE, the UICC containing the USIM is removed, the entry of the "list of subscriber data" with the SNPN identity of the current SNPN is updated, or the rejected S-NSSAI(s) are removed or deleted as described in subclause 4.6.1 and 4.6.2.2.
"S-NSSAI not available due to maximum number of UEs reached"
Unless the back-off timer value received along with the S-NSSAI is zero, the UE shall add the rejected S-NSSAI(s) in the rejected NSSAI for the maximum number of UEs reached as specified in subclause 4.6.2.2 and shall not attempt to use this S-NSSAI in the current PLMN or SNPN over the current access until switching off the UE, the UICC containing the USIM is removed, the entry of the "list of subscriber data" with the SNPN identity of the current SNPN is updated, or the rejected S-NSSAI(s) are removed as described in subclause 4.6.2.2.
NOTE 15: If the back-off timer value received along with the S-NSSAI in the rejected NSSAI for the maximum number of UEs reached is zero as specified in subclause 10.5.7.4a of TS 24.008, the UE does not consider the S-NSSAI as the rejected S-NSSAI.
If there is one or more S-NSSAIs in the rejected NSSAI with the rejection cause "S-NSSAI not available due to maximum number of UEs reached", then for each S-NSSAI, the UE shall behave as follows:
a) stop the timer T3526 associated with the S-NSSAI, if running;
b) start the timer T3526 with:
1) the back-off timer value received along with the S-NSSAI, if a back-off timer value is received along with the S-NSSAI that is neither zero nor deactivated; or
2) an implementation specific back-off timer value, if no back-off timer value is received along with the S-NSSAI; and
c) remove the S-NSSAI from the rejected NSSAI for the maximum number of UEs reached when the timer T3526 associated with the S-NSSAI expires.
[TS 24.501, clause 10.2]
Table 10.2.1: Timers of 5GS mobility management – UE side
|
TIMER NUM. |
TIMER VALUE |
STATE |
CAUSE OF START |
NORMAL STOP |
ON |
|---|---|---|---|---|---|
|
T3526 |
NOTE 9 |
5GMM-DEREGISTERED 5GMM-REGISTERED |
Rejected S-NSSAI with rejection cause "maximum number of UEs per network slice reached" received. |
The associated rejected S-NSSAI for the maximum number of UEs reached as specified in subclause 4.6.2.2 deleted. |
Remove the S-NSSAI in the rejected NSSAI for the maximum number of UEs reached associated with the T3526 timer. |
|
… NOTE 9: The value of this timer is provided by the network operator during the registration procedure or the generic UE configuration update procedure along with the rejected S-NSSAI with rejection cause "maximum number of UEs per network slice reached". The default value of this timer is implementation specific with a minimum value of 12 minutes and used if the network does not provide a value in the REGISTRATION ACCEPT message, the REGISTRATION REJECT message, or the CONFIGURATION UPDATE COMMAND message along with the rejected S-NSSAI with rejection cause "maximum number of UEs per network slice reached". … |
|||||
9.1.12.2.3 Test description
9.1.12.2.3.1 Pre-test conditions
System Simulator:
NGC Cell A belongs to Home PLMN and TAI1 and set as serving cell;
UE:
– UE is previously registered on NGC Cell A using default message contents according to TS 38.508-1 [4];
Preamble:
The UE is in state Switched OFF (state 0N-B) according to TS 38.508-1 [4].
9.1.12.2.3.2 Test procedure sequence
Table 9.1.12.2.3.2-1: Main behaviour
|
St |
Procedure |
Message Sequence |
TP |
Verdict |
|
|
U – S |
Message |
||||
|
1 |
The UE is switched on. |
– |
– |
– |
– |
|
2 |
The UE transmits a REGISTRATION REQUEST message including ER-NSSAI bit |
–> |
REGISTRATION REQUEST |
– |
– |
|
3-11 |
Steps 5 to 13 of the generic procedure for NR RRC_IDLE specified in TS 38.508-1 subclause 4.5.2 are performed. |
– |
– |
– |
– |
|
12 |
The SS transmits a REGISTRATION ACCEPT message including S-NSSAI=1 in extended rejected NSSAI without back-off timer and S-NSSAI=2 in extended rejected NSSAI with back-off timer set to zero Note: Now UE should start timer T3526 associated with S-NSSAI=1 |
<– |
REGISTRATION ACCEPT |
– |
– |
|
13 |
The UE transmits an ULInformationTransfer message and a REGISTRATION COMPLETE message. |
–> |
REGISTRATION COMPLETE |
– |
– |
|
EXCEPTION: Step 14a1 is performed if pc_noOf_PDUsSameConnection > 0. |
|||||
|
14a1 |
The generic procedure for UE-requested PDU session establishment, specified in subclause 4.5A.2, takes place performing establishment of UE-requested PDU session(s) with ExpectedNumberOfNewPDUSessions = pc_noOf_PDUsSameConnection. |
– |
– |
– |
– |
|
15 |
SS releases the RRC connection |
– |
– |
– |
– |
|
16 |
Check: Is S-NSSAI=1 in the Rejected NSSAI list with cause ‘S-NSSAI not available due to maximum number of UEs reached’’ associated with current PLMN using AT/MMI command (+C5GNSSAIRDP)? |
– |
– |
1 |
P |
|
17 |
Cause the UE to request establishment of PDU session with S-NSSAI=1.(Note 1) |
– |
– |
– |
– |
|
18 |
Check: Does the UE transmit an RRCSetupRequest message within T3526 associated with S-NSSAI=1 in the next 30 seconds? |
–> |
NR RRC: RRCSetupRequest |
1 |
F |
|
19 |
Check: Using AT/MMI command (+C5GNSSAIRDP) verify that S-NSSAI=2 is not in the Rejected NSSAI list associated with current PLMN |
2 |
P |
||
|
Note1: The request to establish a PDU session may be performed by MMI or AT Command. |
|||||
9.1.12.2.3.3 Specific message contents
Table 9.1.12.2.3.3-1: REGISTRATION REQUEST (step 2, Table 9.1.12.2.3.2-1)
|
Derivation path: TS 38.508-1 Table 4.7.1-6 |
||||
|
Information Element |
Value/remark |
Comment |
Condition |
|
|
5GS registration type value |
‘001’B |
Initial registration |
||
|
5GMM capability |
||||
|
ER-NSSAI |
‘1’B |
Extended rejected NSSAI supported |
||
Table 9.1.12.2.3.3-2: REGISTRATION ACCEPT (step 12, Table 9.1.12.2.3.2-1)
|
Derivation path: TS 38.508-1 Table 4.7.1-7 |
||||
|
Information Element |
Value/remark |
Comment |
Condition |
|
|
5GS registration result |
||||
|
5GS registration result value |
‘001’B |
3GPP access |
||
|
Allowed NSSAI |
||||
|
S-NSSAI IEI |
S-NSSAI value 3 |
|||
|
Length of S-NSSAI contents |
‘00000001’B |
SST |
||
|
SST |
‘00000011’B |
SST value 3 |
||
|
SD |
Not Present |
|||
|
Mapped configured SST |
Not Present |
|||
|
Mapped configured SD |
Not Present |
|||
|
Configured NSSAI |
||||
|
S-NSSAI IEI |
S-NSSAI value 1 |
|||
|
Length of S-NSSAI contents |
‘00000001’B |
SST |
||
|
SST |
‘00000001’B |
SST value 1 |
||
|
SD |
Not Present |
|||
|
Mapped configured SST |
Not Present |
|||
|
Mapped configured SD |
Not Present |
|||
|
S-NSSAI IEI |
S-NSSAI value 2 |
|||
|
Length of S-NSSAI contents |
‘00000001’B |
SST |
||
|
SST |
‘00000010’B |
SST value 2 |
||
|
SD |
Not Present |
|||
|
Mapped configured SST |
Not Present |
|||
|
Mapped configured SD |
Not Present |
|||
|
Extended rejected NSSAI |
||||
|
Length of Extended rejected NSSAI contents |
2 entries |
|||
|
Partial extended rejected NSSAI list |
entry 1 |
|||
|
Type of list |
‘000’B |
S-NSSAI without any associated back-off timer value |
||
|
Number of elements |
‘0000’B |
1 element |
||
|
Rejected S-NSSAI 1 |
S-NSSAI value 1 |
|||
|
Length of rejected S-NSSAI |
‘00000001’B |
SST |
||
|
Cause value |
‘0011’B |
S-NSSAI not available due to maximum number of UEs reached |
||
|
SST |
‘00000001’B |
SST value 1 |
||
|
SD |
Not Present |
|||
|
Mapped HPLMN SST |
Not present |
|||
|
Mapped HPLMN SD |
Not present |
|||
|
Partial extended rejected NSSAI list |
entry 2 |
|||
|
Type of list |
‘001’B |
S-NSSAIs with back-off timer |
||
|
Number of elements |
‘0000’B |
1 element |
||
|
Back-off timer value |
’00000000’B |
0 |
||
|
Rejected S-NSSAI 1 |
S-NSSAI value 2 |
|||
|
Length of rejected S-NSSAI |
‘00000001’B |
SST |
||
|
Cause value |
‘0011’B |
S-NSSAI not available due to maximum number of UEs reached |
||
|
SST |
‘00000010’B |
SST value 2 |
||
|
SD |
Not Present |
|||
|
Mapped HPLMN SST |
Not present |
|||
|
Mapped HPLMN SD |
Not present |
|||
9.1.12.3 NSAC / Initial registration / Rejected / equivalent PLMNs
9.1.12.3.1 Test Purpose (TP)
(1)
with { UE in 5GMM-REGISTERED-INITIATED state}
ensure that {
when { UE receives the rejected NSSAI in the REGISTRATION REJECT message with rejection cause of “S-NSSAI not available due to maximum number of UEs reached}
then { UE shall stores the rejected NSSAI and start the timer T3526}
}
(2)
with { UE receives rejected NSSAI with rejection cause of “S-NSSAI not available due to maximum number of UEs reached”}
ensure that {
when { UE selectes to the equivalent PLMN in the same registration area}
then { UE shall treat the received rejected NSSAI for the maximum number of UEs reached as applicable to equivalent PLMNs}
}
(3)
with { UE receives rejected NSSAI with rejection cause of “S-NSSAI not available due to maximum number of UEs reached”}
ensure that {
when { UE timer T3526 expires}
then { Remove the S-NSSAI in the rejected NSSAI for the maximum number of UEs reached and initiates a registration procedure}
}
9.1.12.3.2 Conformance requirements
References: The conformance requirements covered in the current TC are specified in: TS 24.501, clauses 5.5.1.2.5, 4.6.1. Unless otherwise stated these are Rel-17 requirements
[TS 24.501, clause 5.5.1.2.5]
#62 (No network slices available).
The UE shall abort the initial registration procedure, set the 5GS update status to 5U2 NOT UPDATED and enter state 5GMM-DEREGISTERED. ATTEMPTING-REGISTRATION or 5GMM-DEREGISTERED.PLMN-SEARCH. Additionally, the UE shall reset the registration attempt counter.
The UE receiving the rejected NSSAI in the REGISTRATION REJECT message takes the following actions based on the rejection cause in the rejected S-NSSAI(s):
"S-NSSAI not available in the current PLMN or SNPN"
The UE shall store the rejected S-NSSAI(s) in the rejected NSSAI for the current PLMN or SNPN as specified in subclause 4.6.2.2 and shall not attempt to use this S-NSSAI(s) in the current PLMN or SNPN until switching off the UE, the UICC containing the USIM is removed, an entry of the "list of subscriber data" with the SNPN identity of the current SNPN is updated, or the rejected S-NSSAI(s) are removed or deleted as described in subclause 4.6.2.2.
"S-NSSAI not available in the current registration area"
The UE shall store the rejected S-NSSAI(s) in the rejected NSSAI for the current registration area as described in subclause 4.6.2.2 and shall not attempt to use this S-NSSAI(s) in the current registration area until switching off the UE, the UE moving out of the current registration area, the UICC containing the USIM is removed, the entry of the "list of subscriber data" with the SNPN identity of the current SNPN is updated, or the rejected S-NSSAI(s) are removed or deleted as described in subclause 4.6.2.2.
"S-NSSAI not available due to the failed or revoked network slice-specific authentication and authorization"
The UE shall store the rejected S-NSSAI(s) in the rejected NSSAI for the failed or revoked NSSAA as specified in subclause 4.6.2.2 and shall not attempt to use this S-NSSAI in the current PLMN or SNPN over any access until switching off the UE, the UICC containing the USIM is removed, the entry of the "list of subscriber data" with the SNPN identity of the current SNPN is updated, or the rejected S-NSSAI(s) are removed or deleted as described in subclause 4.6.1 and 4.6.2.2.
"S-NSSAI not available due to maximum number of UEs reached"
Unless the back-off timer value received along with the S-NSSAI is zero, the UE shall add the rejected S-NSSAI(s) in the rejected NSSAI for the maximum number of UEs reached as specified in subclause 4.6.2.2 and shall not attempt to use this S-NSSAI in the current PLMN or SNPN over the current access until switching off the UE, the UICC containing the USIM is removed, the entry of the "list of subscriber data" with the SNPN identity of the current SNPN is updated, or the rejected S-NSSAI(s) are removed as described in subclause 4.6.2.2.
NOTE 6: If the back-off timer value received along with the S-NSSAI in the rejected NSSAI for the maximum number of UEs reached is zero as specified in subclause 10.5.7.4a of TS 24.008, the UE does not consider the S-NSSAI as the rejected S-NSSAI.
If there is one or more S-NSSAIs in the rejected NSSAI with the rejection cause "S-NSSAI not available due to maximum number of UEs reached", then for each S-NSSAI, the UE shall behave as follows:
a) stop the timer T3526 associated with the S-NSSAI, if running;
b) start the timer T3526 with:
1) the back-off timer value received along with the S-NSSAI, if a back-off timer value is received along with the S-NSSAI that is neither zero nor deactivated; or
2) an implementation specific back-off timer value, if no back-off timer value is received along with the S-NSSAI; and
c) remove the S-NSSAI from the rejected NSSAI for the maximum number of UEs reached when the timer T3526 associated with the S-NSSAI expires.
If the UE has an allowed NSSAI or configured NSSAI that contains S-NSSAI(s) which are not included in the rejected NSSAI the UE may stay in the current serving cell, apply the normal cell reselection process and start an initial registration with a requested NSSAI that includes any S-NSSAI from the allowed NSSAI or the configured NSSAI that is not in the rejected NSSAI. Otherwise the UE may perform a PLMN selection or SNPN selection according to 3GPP TS 23.122 [5] and additionally, the UE may disable the N1 mode capability for the current PLMN or SNPN if the UE does not have an allowed NSSAI and each S-NSSAI in configured NSSAI, if available, was rejected with cause "S-NSSAI not available in the current PLMN or SNPN" or "S-NSSAI not available due to the failed or revoked network slice-specific authentication and authorization" as described in subclause 4.9.
If the UE has neither allowed NSSAI for the current PLMN or SNPN nor configured NSSAI for the current PLMN or SNPN and,
1) if at least one S-NSSAI in the default configured NSSAI is not rejected, the UE may stay in the current serving cell, apply the normal cell reselection process, and start an initial registration with a requested NSSAI with that default configured NSSAI; or
2) if all the S-NSSAI(s) in the default configured NSSAI are rejected and at least one S-NSSAI is rejected due to "S-NSSAI not available in the current registration area",
i) if the REGISTRATION REJECT message is integrity protected and the UE is not operating in SNPN access operation mode, the UE shall store the current TAI in the list of "5GS forbidden tracking areas for roaming" and enter the state 5GMM-DEREGISTERED.LIMITED-SERVICE; or
ii) if the REGISTRATION REJECT message is integrity protected and the UE is operating in SNPN access operation mode, the UE shall store the current TAI in the list of "5GS forbidden tracking areas for roaming" for the current SNPN and enter the state 5GMM-DEREGISTERED.LIMITED-SERVICE.
Otherwise, the UE may perform a PLMN selection or SNPN selection according to 3GPP TS 23.122 [5] and additionally, the UE may disable the N1 mode capability for the current PLMN or SNPN if each S-NSSAI in the default configured NSSAI was rejected with cause "S-NSSAI not available in the current PLMN or SNPN" or "S-NSSAI not available due to the failed or revoked network slice-specific authentication and authorization" as described in subclause 4.9.
If the UE has neither allowed NSSAI for the current PLMN or SNPN nor configured NSSAI for the current PLMN or SNPN and has rejected NSSAI for the reached maximum number of UEs, and the UE wants to obtain services in the current serving cell without performing a PLMN selection or SNPN selection, the UE may stay in the current serving cell and attempt to use the rejected S-NSSAI(s) for the maximum number of UEs reached in the current serving cell after the rejected S-NSSAI(s) are removed as described in subclause 4.6.2.2.
If the message was received via 3GPP access and the UE is operating in single-registration mode, the UE shall in addition set the EPS update status to EU2 NOT UPDATED, reset the attach attempt counter and enter the state EMM-DEREGISTERED.
[TS 24.501, clause 4.1.6.2]
The rejected NSSAI for the maximum number of UEs reached is applicable for the whole registered PLMN or SNPN, and the access type over which the rejected NSSAI was sent. The AMF shall send a rejected NSSAI including S-NSSAI(s) with the rejection cause "S-NSSAI not available due to maximum number of UEs reached", when one or more S-NSSAIs are indicated that the maximum number of UEs has been reached. If the timer T3526 associated with the S-NSSAI(s) was started upon reception of the rejected NSSAI for the maximum number of UEs reached, the UE may remove the S-NSSAI(s) from the rejected NSSAI including S-NSSAI(s) with the rejection cause "S-NSSAI not available due to maximum number of UEs reached", if the timer T3526 associated with the S-NSSAI(s) expires. If one or more S-NSSAIs are removed from the rejected NSSAI for the maximum number of UEs reached, the timer T3526 associated with the removed S-NSSAI(s) shall be stopped, if running. The UE shall not stop the timer T3526 if the UE selects an E-UTRA cell connected to EPC.
If the UE receives a rejected NSSAI for the maximum number of UEs reached, the registration area contains TAIs belonging to different PLMNs, which are equivalent PLMNs, the UE shall treat the received rejected NSSAI for the maximum number of UEs reached as applicable to these equivalent PLMNs when the UE is in this registration area.
[TS 24.501, clause 10.2]
Table 10.2.1: Timers of 5GS mobility management – UE side
|
TIMER NUM. |
TIMER VALUE |
STATE |
CAUSE OF START |
NORMAL STOP |
ON |
|---|---|---|---|---|---|
|
T3502 |
Default 12 min. NOTE 1 |
5GMM-DEREGISTERED 5GMM-REGISTERED |
At registration failure and the attempt counter is equal to 5 |
Transmission of REGISTRATION REQUEST message |
Initiation of the registration procedure, if still required |
|
… |
|||||
|
T3526 |
NOTE 9 |
5GMM-DEREGISTERED 5GMM-REGISTERED |
Rejected S-NSSAI with rejection cause "maximum number of UEs per network slice reached" received. |
The associated rejected S-NSSAI for the maximum number of UEs reached as specified in subclause 4.6.2.2 deleted. |
Remove the S-NSSAI in the rejected NSSAI for the maximum number of UEs reached associated with the T3526 timer. |
9.1.12.3.3 Test description
9.1.12.3.3.1 Pre-test conditions
System Simulator:
– NGC Cell A (home PLMN) and NGC Cell E are configured according to Table 6.3.2.2-1 in TS 38.508-1 [4].
– System information combination NR-2 in accordance with TS 38.508-1 [4] sub-clause 4.4.3.1.2 is used in NGC Cell A and NGC Cell E.
– The UE is last authenticated and registered on NGC Cell A and Cell E PLMN is provided as equivalent PLMN.
Preamble:
– The UE is in state Switched OFF (state 0N-B) according to TS 38.508-1 [4].
9.1.12.3.3.2 Test procedure sequence
Table 9.1.12.3.3.2-1: Main behaviour
|
St |
Procedure |
Message Sequence |
TP |
Verdict |
|
|
U – S |
Message |
||||
|
1 |
The SS configures: – NGC Cell A as the "Serving cell ". – NGC Cell E as “Non-suitable "Off" cell”. |
– |
– |
– |
– |
|
2 |
The UE is switched on. |
– |
– |
– |
– |
|
3-14 |
Steps 2-13 of Table 4.5.2.2-2 of the generic procedure in TS 38.508-1 [4] are performed. |
– |
– |
– |
– |
|
15 |
The SS transmits a REGISTRATION REJECT message, 5GMM cause value = #62 "No network slices available" and rejection cause in the Extended rejected S-NSSAI is set =’0011’B “S-NSSAI not available due to maximum number of UEs reached”, T3526 is not present default value of 12 minutes is applied. |
<– |
REGISTRATION REJECT |
– |
– |
|
16 |
SS starts timer of t_Waits= T3526. |
– |
– |
– |
– |
|
17 |
The SS releases the RRC connection. |
– |
– |
– |
– |
|
18 |
Check: Does the UE transmit the REGISTRATION REQUEST message on NGC Cell A in the next 30 seconds? |
–> |
REGISTRATION REQUEST |
1 |
F |
|
19 |
The SS reconfigures: – NGC cell E as the "Serving cell". – NGC cell A as a "Non-suitable "Off" cell". |
– |
– |
– |
– |
|
20 |
Check: Does the UE transmit the REGISTRATION REQUEST message on NGC Cell E in the next 60 seconds? |
–> |
REGISTRATION REQUEST |
2 |
F |
|
21 |
SS waits for the expiration of t_Waits.. |
– |
– |
– |
– |
|
22 |
Check: Does the UE transmit a REGISTRATION REQUEST message on NGC Cell A? |
–> |
REGISTRATION REQUEST |
3 |
P |
|
23-38a1 |
Steps 5-20a1 of Table 4.5.2.2-2 in TS38.508-1 [4] are performed. |
– |
– |
– |
– |
9.1.12.3.3.3 Specific message contents
Table 9.1.12.3.3.3-1: REGISTRATION REJECT (step 15, Table 9.1.12.3.3.2-1)
|
Derivation path: TS 38.508-1 [4] table 4.7.1-9 |
|||
|
Information Element |
Value/remark |
Comment |
Condition |
|
5GMM cause |
‘0011 1110’B |
#62 “No network slices available” |
|
|
Extended rejected NSSAI |
|||
|
Extended rejected NSSAI IEI |
|||
|
Length of Extended rejected NSSAI contents |
‘0101’B |
||
|
Length of Extended rejected S-NSSAI |
‘0100’B |
SST |
|
|
Cause value |
‘0011’B |
S-NSSAI not available due to maximum number of UEs reached. |
|
|
SST |
‘00000001’B |
SST value 1 |
|
|
SD |
’FFFFFF’H |
no SD value associated with the SST |
|