22.5.4 NB-IoT / Attach to new PLMN IMSI / Network reject with Extended Wait Timer / Paging with IMSI / Attach Rejected Illegal ME/UE / Detach upon switch-off

36.523-13GPPEvolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Packet Core (EPC)Part 1: Protocol conformance specificationRelease 17TSUser Equipment (UE) conformance specification

22.5.4.1 Test Purpose (TP)

(1)

with { the UE switched-off after registering to a PLMN }

ensure that {

when { UE is powered on in a cell not belonging to the last visited registered PLMN which is not in the UE’s list of equivalent PLMNs nor in the UE’s list with TAIs }

then { the UE successfully attaches to the new PLMN (IMSI) }

}

(2)

with { UE in RRC-IDLE/EMM-REGISTERED }

ensure that {

when { the UE receives a Paging message with IMSI }

then { the UE detaches locally and performs re-attach }

}

(3)

with { UE has sent an ATTACH REQUEST message including a PDN CONNECTIVITY REQUEST message }

ensure that {

when { UE receives an ATTACH REJECT message with the reject cause set to "Illegal UE" or "Illegal ME" }

then { UE considers the USIM as invalid for EPS services until switching off or the UICC containing the USIM is removed }

}

(4)

with { UE operating in NB-S1 mode, having sent an ATTACH REQUEST message }

ensure that {

when { UE receives "Extended wait time" from the lower layers (due to reception of RRCConnectionRelease message indicating “Extended Wait Time” }

then { UE aborts the attach procedure, starts timer T3346, and, restarts attach procedure after timer T3346 expires }

}

(5)

with { the UE in RRC-IDLE/EMM-REGISTERED }

ensure that {

when { UE is switched off }

then { the UE performs a detach procedure }

}

22.5.4.2 Conformance requirements

References: The conformance requirements covered in the current TC are specified in: TS 24.301 clauses 5.5.1.2.2, 5.5.1.2.4, 5.5.1.2.5, 5.5.1.2.6, 5.5.2.2.1, 5.6.2.2.2 and TS 36.331 clause 5.3.8.3. Unless otherwise stated these are Rel-13 requirements.

[TS 24.301, clause 5.5.1.2.2]

In state EMM-DEREGISTERED, the UE initiates the attach procedure by sending an ATTACH REQUEST message to the MME, starting timer T3410 and entering state EMM-REGISTERED-INITIATED (see example in figure 5.5.1.2.2.1). If timer T3402 is currently running, the UE shall stop timer T3402. If timer T3411 is currently running, the UE shall stop timer T3411.

The UE shall include the IMSI in the EPS mobile identity IE in the ATTACH REQUEST message if the selected PLMN is neither the registered PLMN nor in the list of equivalent PLMNs and:

– the UE is configured for "AttachWithIMSI" as specified in 3GPP TS 24.368 [15A] or 3GPP TS 31.102 [17]; or

– the UE is in NB-S1 mode.

For all other cases, the UE shall handle the EPS mobile identity IE in the ATTACH REQUEST message as follows:

If the UE supports neither A/Gb mode nor Iu mode:

– the UE shall include in the ATTACH REQUEST message a valid GUTI together with the last visited registered TAI, if available. In addition, the UE shall include Old GUTI type IE with GUTI type set to "native GUTI". If there is no valid GUTI available, the UE shall include the IMSI in the ATTACH REQUEST message.

[TS 24.301, clause 5.5.1.2.4]

During an attach for emergency bearer services, if not restricted by local regulations, the MME shall not check for mobility and access restrictions, regional restrictions, subscription restrictions, or perform CSG access control when processing the ATTACH REQUEST message. The network shall not apply subscribed APN based congestion control during an attach procedure for emergency bearer services.

If the attach request is accepted by the network, the MME shall send an ATTACH ACCEPT message to the UE and start timer T3450.

Upon receiving the ATTACH ACCEPT message, the UE shall stop timer T3410.

The GUTI reallocation may be part of the attach procedure. When the ATTACH REQUEST message includes the IMSI or IMEI, or the MME considers the GUTI provided by the UE is invalid, or the GUTI provided by the UE was assigned by another MME, the MME shall allocate a new GUTI to the UE. The MME shall include in the ATTACH ACCEPT message the new assigned GUTI together with the assigned TAI list. In this case the MME shall enter state EMM-COMMON-PROCEDURE-INITIATED as described in subclause 5.4.1.

If the ATTACH ACCEPT message contains a GUTI, the UE shall use this GUTI as the new temporary identity. The UE shall delete its old GUTI and store the new assigned GUTI. If no GUTI has been included by the MME in the ATTACH ACCEPT message, the old GUTI, if any available, shall be kept.

[TS 24.301, clause 5.5.1.2.5]

If the attach request cannot be accepted by the network, the MME shall send an ATTACH REJECT message to the UE including an appropriate EMM cause value.

The UE shall take the following actions depending on the EMM cause value received in the ATTACH REJECT message.

#3 (Illegal UE);

#6 (Illegal ME); or

The UE shall set the EPS update status to EU3 ROAMING NOT ALLOWED (and shall store it according to subclause 5.1.3.3) and shall delete any GUTI, last visited registered TAI, TAI list and eKSI. The UE shall consider the USIM as invalid for EPS services and non-EPS services until switching off or the UICC containing the USIM is removed or the timer T3245 expires as described in subclause 5.3.7a. Additionally, the UE shall delete the list of equivalent PLMNs and enter state EMM-DEREGISTERED.

[TS 24.301, clause 5.5.1.2.6]

The following abnormal cases can be identified:

l) "Extended wait time" from the lower layers

If the ATTACH REQUEST message contained the low priority indicator set to "MS is configured for NAS signalling low priority", the UE shall start timer T3346 with the "Extended wait time" value and reset the attach attempt counter.

If the ATTACH REQUEST message did not contain the low priority indicator set to "MS is configured for NAS signalling low priority" and the UE is operating in NB-S1 mode, then the UE shall start timer T3346 with the "Extended wait time" value and reset the attach attempt counter.

The UE shall abort the attach procedure, stay in the current serving cell, change the state to EMM-DEREGISTERED.ATTEMPTING-TO-ATTACH and apply the normal cell reselection process.

The UE shall proceed as described below.

m) Timer T3346 is running

The UE shall not start the attach procedure unless:

– the UE is a UE configured to use AC11 – 15 in selected PLMN;

– the UE needs to attach for emergency bearer services; or

– the UE needs to attach without the NAS signalling low priority indication and if the timer T3346 was started due to rejection of a NAS request message (e.g. ATTACH REQUEST, TRACKING AREA UPDATE REQUEST or EXTENDED SERVICE REQUEST) which contained the low priority indicator set to "MS is configured for NAS signalling low priority".

The UE stays in the current serving cell and applies the normal cell reselection process.

NOTE 4: It is considered an abnormal case if the UE needs to initiate an attach procedure while timer T3346 is running independent on whether timer T3346 was started due to an abnormal case or a non successful case.

The UE shall proceed as described below.

For the cases b, c, d, l and m:

– Timer T3410 shall be stopped if still running.

– …

– If the attach attempt counter is less than 5:

– for the cases l and m, the attach procedure is started, if still necessary, when timer T3346 expires or is stopped;

[TS 36.331, clause 5.3.8.3]

The UE shall:

1> for NB-IoT, delay the following actions defined in this sub-clause 10 seconds from the moment the RRCConnectionRelease message was received or optionally when lower layers indicate that the receipt of the RRCConnectionRelease message has been successfully acknowledged, whichever is earlier;

1> else:

2> if the extendedWaitTime is present; and

2> if the UE supports delay tolerant access or the UE is a NB-IoT UE:

3> forward the extendedWaitTime to upper layers;

[TS 24.301, clause 5.5.2.2.1]

The detach procedure is initiated by the UE by sending a DETACH REQUEST message (see example in figure 5.5.2.2.1.1). The Detach type IE included in the message indicates whether detach is due to a "switch off" or not. The Detach type IE also indicates whether the detach is for EPS services only, for non-EPS services only, or for both. If the UE has a mapped EPS security context as the current EPS security context, the UE shall set the type of security context flag to "mapped security context". Otherwise, the UE shall set the type of security context flag to "native security context".

If the UE has a valid GUTI, the UE shall populate the EPS mobile identity IE with the valid GUTI. If the UE does not have a valid GUTI, the UE shall populate the EPS mobile identity IE with its IMSI.

If the UE does not have a valid GUTI and it does not have a valid IMSI, then the UE shall populate the EPS mobile identity IE with its IMEI.

If the UE is to be switched off, the UE shall try for a period of 5 seconds to send the DETACH REQUEST message. During this period, the UE may be switched off as soon as the DETACH REQUEST message has been sent.

After the last DETACH REQUEST message is sent, the UE shall proceed as follows:

– if the current EPS security context is a native EPS security context, then the UE shall store the current EPS security context as specified in annex C and mark it as valid;

[TS 24.301, clause 5.6.2.2.2]

Paging for EPS services using IMSI is an abnormal procedure used for error recovery in the network.

When a UE receives a paging for EPS services using IMSI from the network before a UE initiated EMM specific procedure has been completed, then the UE shall abort the EMM specific procedure and proceed according to the description in this subclause.

Upon reception of a paging for EPS services using IMSI, the UE shall stop timer T3346, if it is running, locally deactivate any EPS bearer context(s), if any, and locally detach from EPS. Additionally the UE shall delete the following parameters: last visited registered TAI, TAI list, GUTI and KSIASME. The UE shall set the EPS update status to EU2 NOT UPDATED and change the state to EMM-DEREGISTERED. The UE shall stop all timers T3396 that are running.

After performing the local detach, the UE shall then perform an attach procedure as described in subclause 5.5.1.2. If the UE is operating in CS/PS mode 1 or CS/PS mode 2 of operation, then the UE shall perform a combined attach procedure as described in subclause 5.5.1.3.

NOTE 1: In some cases, user interaction can be required, thus the UE cannot activate the dedicated bearer context(s), if any, automatically.

NOTE 2: The UE does not respond to the paging except with the ATTACH REQUEST message, hence timers T3413 and T3415 in the network are not used when paging with IMSI.

22.5.4.3 Test description

22.5.4.3.1 Pre-test conditions

System Simulator:

– 2 NB-IoT cells, default system information

– Ncell 1 "Serving cell", PLMN1, TAI-1

– Ncell 12 "Non-Suitable cell", PLMN2, TAI-3

UE:

None.

Preamble:

– The UE is made register on NB-IoT Ncell 1 and enter State 3-NB "Registered, Idle Mode" according to TS 36.508 [18]; during the attach GUTI-1 is assigned, PLMN2 is not included in the equivalent PLMN list , nor TAI-3 in the TAI list assigned.

– After registration the UE is switched off in order to enter State 1-NB "Switched OFF" according to TS 36.508 [18].

22.5.4.3.2 Test procedure sequence

Table 22.5.4.3.2-1: Main behaviour

St

Procedure

Message Sequence

TP

Verdict

U – S

Message

1

The SS configures:

– Ncell 1 as a "Non-Suitable cell".

– Ncell 12 as the "Serving cell".

2

Switch on the UE

3

Check: Does the UE transmit an RRCConnectionRequest-NB message?

–>

RRC: RRCConnectionRequest-NB

1

P

4

SS transmits an RRCConnectionSetup-NB.

<–

RRC: RRCConnectionSetup-NB

EXCEPTION: Steps 5a1 and 5b1 describe behaviour that depends on UE capabilities; the "lower case letter" identifies a step sequence that take place depending on whether the UE is configured to do Attach Without PDN or not.

5a1

IF px_DoAttachWithoutPDN THEN

Check: Does the UE transmit an RRCConnectionSetupComplete-NB message containing an ATTACH REQUEST message (indicating IMSI as previously registered GUTI was on a differerent PLMN and KSI as per the registration which happened in the preamble), and, an ESM DUMMY MESSAGE?

–>

RRC: RRCConnectionSetupComplete-NB

NAS: ATTACH REQUEST

NAS: ESM DUMMY MESSAGE

1

P

5b1

ELSE

Check: Does the UE transmit an RRCConnectionSetupComplete-NB message containing an ATTACH REQUEST message (indicating IMSI as previously registered GUTI was on a differerent PLMN and KSI as per the registration which happened in the preamble), and, a PDN CONNECTIVITY REQUEST?

–>

RRC: RRCConnectionSetupComplete-NB

NAS: ATTACH REQUEST

NAS: PDN CONNECTIVITY REQUEST

1

P

6

The SS transmits an RRCConnectionRelease-NB message including the IE “Extended Wait Time” set to 25 seconds.

<–

RRC: RRCConnectionRelease-NB

7

The SS waits 25 seconds (Extended wait timer value).

8

Check: Does the UE transmit an RRCConnectionRequest-NB message?

–>

RRC: RRCConnectionRequest-NB

4

P

9

SS transmits an RRCConnectionSetup-NB.

<–

RRC: RRCConnectionSetup-NB

EXCEPTION: Steps 10a1 and 10b1 describe behaviour that depends on UE capabilities; the "lower case letter" identifies a step sequence that take place depending on whether the UE is configured to do Attach Without PDN or not.

10a1

IF px_DoAttachWithoutPDN THEN

Check: Does the UE transmit an RRCConnectionSetupComplete-NB message containing an ATTACH REQUEST message (indicating IMSI as previously registered GUTI was on a different PLMN and KSI as per the registration which happened in the preamble), and, an ESM DUMMY MESSAGE?

–>

RRC: RRCConnectionSetupComplete-NB

NAS: ATTACH REQUEST

NAS: ESM DUMMY MESSAGE

4

P

10b1

ELSE

Check: Does the UE transmit an RRCConnectionSetupComplete-NB message containing an ATTACH REQUEST message (indicating IMSI as previously registered GUTI was on a different PLMN and KSI as per the registration which happened in the preamble), and, a PDN CONNECTIVITY REQUEST?

–>

RRC: RRCConnectionSetupComplete-NB

NAS: ATTACH REQUEST

NAS: PDN CONNECTIVITY REQUEST

4

P

11-20b1

Steps 5-14b1 from the Generic procedure ‘NB-IoT UE Attach, Connected mode (State 2-NB)’ as described in TS 36.508 [18], clause 8.1.5.2 take place.

21

The SS transmits an RRCConnectionRelease-NB message to release RRC connection and move to RRC_IDLE.

<–

RRC: RRCConnectionRelease-NB

22

SS sends a Paging message indicating IMSI as the UE identity.

NOTE: Upon reception of paging with IMSI the UE shall locally deactivate any EPS bearer context(s), locally detach from EPS and delete the GUTI. After local detach the UE shall perform an EPS attach procedure.

<–

RRC: Paging-NB

EXCEPTION: Steps 23a1 describes a behaviour which depends on the UE capability

23a1

IF NOT pc_Automatic_EPS_Re_Attach, the user initiates an attach by MMI or by AT command.

24

Check: Does the UE transmit an RRCConnectionRequest-NB message?

–>

RRC: RRCConnectionRequest-NB

2,3

P

25

SS transmits an RRCConnectionSetup-NB.

<–

RRC: RRCConnectionSetup-NB

EXCEPTION: Steps 26a1 and 26b1 describe behaviour that depends on UE capabilities; the "lower case letter" identifies a step sequence that take place depending on whether the UE is configured to do Attach Without PDN or not.

26a1

IF px_DoAttachWithoutPDN THEN

Check: Does the UE transmit an RRCConnectionSetupComplete-NB message containing an ATTACH REQUEST message (not including any GUTI, last visited registered TAI nor KSI), and an ESM DUMMY MESSAGE?

–>

RRC: RRCConnectionSetupComplete-NB

NAS: ATTACH REQUEST

NAS: ESM DUMMY MESSAGE

2,3

P

26b1

ELSE

Check: Does the UE transmit an RRCConnectionSetupComplete-NB message containing an ATTACH REQUEST message (not including any GUTI, last visited registered TAI nor KSI) and a PDN CONNECTIVITY REQUEST?

–>

RRC: RRCConnectionSetupComplete-NB

NAS: ATTACH REQUEST

NAS: PDN CONNECTIVITY REQUEST

2,3

P

27-36b1

Steps 5-14b1 from the Generic procedure ‘NB-IoT UE Attach, Connected mode (State 2-NB)’ as described in TS 36.508 [18], clause 8.1.5.2 take place.

37

The SS transmits an RRCConnectionRelease-NB message to release RRC connection and move to RRC_IDLE.

<–

RRC: RRCConnectionRelease-NB

38

Switch off the UE

39

The UE transmit an RRCConnectionRequest-NB message.

–>

RRC: RRCConnectionRequest-NB

40

SS transmits an RRCConnectionSetup-NB message.

<–

RRC: RRCConnectionSetup-NB

41

The UE transmit an RRCConnectionSetupComplete-NB message.

–>

RRC: RRCConnectionSetupComplete-NB

42

Check: Does the UE transmit a DETACH REQUEST with the Detach Type IE indicating "switch off"?

–>

RRC: ULInformationTransfer-NB

NAS: DETACH REQUEST

5

P

43

The SS releases the RRC connection.

RRC: RRCConnectionRelease-NB

44

The UE is switched on

45

Check: Does the UE transmit an RRCConnectionRequest-NB message?

–>

RRC: RRCConnectionRequest-NB

5

P

46

SS transmits an RRCConnectionSetup-NB.

<–

RRC: RRCConnectionSetup-NB

EXCEPTION: Steps 47a1 and 47b1 describe behaviour that depends on UE capabilities; the "lower case letter" identifies a step sequence that take place depending on whether the UE is configured to do Attach Without PDN or not.

47a1

IF px_DoAttachWithoutPDN THEN

Check: Does the UE transmit an RRCConnectionSetupComplete-NB message containing an ATTACH REQUEST message (indicating GUTI, last visited registered TAI and KSI as per the registration which happened in steps 23-32b1), and, an ESM DUMMY MESSAGE?

–>

RRC: RRCConnectionSetupComplete-NB

NAS: ATTACH REQUEST

NAS: ESM DUMMY MESSAGE

5

P

47b1

ELSE

Check: Does the UE transmit an RRCConnectionSetupComplete-NB message containing an ATTACH REQUEST message (indicating GUTI, last visited registered TAI and KSI as per the registration which happened in steps 23-32b1), and, a PDN CONNECTIVITY REQUEST?

–>

RRC: RRCConnectionSetupComplete-NB

NAS: ATTACH REQUEST

NAS: PDN CONNECTIVITY REQUEST

5

P

48

The SS transmits an ATTACH REJECT message with EMM cause = "Illegal UE".

<–

RRC: DLInformationTransfer-NB

NAS: ATTACH REJECT

49

The SS transmits an RRCConnectionRelease-NB message to release RRC connection.

<–

RRC: RRCConnectionRelease-NB

49A

SS sends a Paging message to the UE on the appropriate paging block, and including the UE identity in one entry of the IE pagingRecordLists.

<–

RRC: Paging-NB

50

Check: Does the UE respond to paging by transmitting an RRCConnectionRequest-NB message in the next 30 seconds?

–>

RRC: RRCConnectionRequest-NB

3

F

51

The operator initiates an UE attach by MMI or by AT command.

52

Check: Does the UE transmit an ATTACH REQUEST message in the next 30 seconds?

–>

RRC: ULInformationTransfer-NB

NAS: ATTACH REQUEST

3

F

53

If possible (see ICS) switch off is performed or the USIM is removed.

Otherwise the power is removed.

54

The UE is brought back to operation or the USIM is inserted.

55-85

Steps 24-54 are repeated with the only difference that the reject reason in the ATTACH REJECT message sent in step 44 is set to ‘Illegal ME’.

86

Check: Does the UE transmit an RRCConnectionRequest-NB message?

–>

RRC: RRCConnectionRequest-NB

3

P

87

SS transmits an RRCConnectionSetup-NB.

<–

RRC: RRCConnectionSetup-NB

88

EXCEPTION: Steps 89a1 and 89b1 describe behaviour that depends on UE capabilities; the "lower case letter" identifies a step sequence that take place depending on whether the UE is configured to do Attach Without PDN or not.

89a1

IF px_DoAttachWithoutPDN THEN

Check: Does the UE transmit an RRCConnectionSetupComplete-NB message containing an ATTACH REQUEST message (not including any GUTI, last visited registered TAI nor KSI), and an ESM DUMMY MESSAGE?

–>

RRC: RRCConnectionSetupComplete-NB

NAS: ATTACH REQUEST

NAS: ESM DUMMY MESSAGE

3

P

89b1

ELSE

Check: Does the UE transmit an RRCConnectionSetupComplete-NB message containing an ATTACH REQUEST message (not including any GUTI, last visited registered TAI nor KSI) and a PDN CONNECTIVITY REQUEST?

–>

RRC: RRCConnectionSetupComplete-NB

NAS: ATTACH REQUEST

NAS: PDN CONNECTIVITY REQUEST

3

P

90-99b1

Steps 5-14b1 from the Generic procedure ‘NB-IoT UE Attach, Connected mode (State 2-NB)’ as described in TS 36.508 [18], clause 8.1.5.2 take place.

100

The SS transmits an RRCConnectionRelease-NB message to release RRC connection and move to RRC_IDLE.

<–

RRC: RRCConnectionRelease-NB

22.5.4.3.3 Specific message contents

Table 22.5.4.3.3-1: SystemInformationBlockType1-NB (Preamble and all steps)

Derivation Path: 36.508 [18], Table 8.1.4.3.2-3, condition ATTACH_WITHOUT_PDN

Table 22.5.4.3.3-2: Message RRCConnectionRequest-NB (steps 3, 7, 24, 45, 55, 76, 86, Table 22.5.4.3.2-1)

Derivation path: TS 36.508 [18], Table 8.1.6.1-10

Information Element

Value/Remark

Comment

Condition

RRCConnectionRequest-NB ::= SEQUENCE {

criticalExtensions CHOICE {

rrcConnectionRequest-r13 SEQUENCE {

establishmentCause-r13

mo-Signalling

}

}

}

Table 22.5.4.3.3-3: Message ATTACH REQUEST (steps 5a1, 5b1, 10a1, 10b1, Table 22.5.4.3.2-1)

Derivation path: TS 36.508 [18], Table 4.7.2-4

Information Element

Value/Remark

Comment

Condition

NAS key set identifier

TSC

‘0’B

native security context

NAS key set identifier

The value is the same value to be allocated by SS in the Preamble.

Old GUTI or IMSI

IMSI

Last visited registered TAI

TAI-1 if present

Table 22.5.4.3.3-4: Paging-NB (step 22, Table 22.5.4.3.2-1)

Derivation Path: TS 36.508 [18], Table 4.6.1-7

Information Element

Value/remark

Comment

Condition

Paging-NB ::= SEQUENCE {

pagingRecordList SEQUENCE (SIZE (1..maxPageRec)) OF SEQUENCE {

1 entry

ue-Identity[1] CHOICE {

IMSI

Set to the value of the IMSI of the UE

}

}

}

Table 22.5.4.3.3-5: Message ATTACH REQUEST (steps 26a1, 26b1, 57a1, 57b1, 89a1, 89b1, Table 22.5.4.3.2-1)

Derivation path: TS 36.508 [18], Table 4.7.2-4

Information Element

Value/Remark

Comment

Condition

NAS key set identifier

111

"No key is available"

Old GUTI or IMSI

IMSI

Last visited registered TAI

Not present

Table 22.5.4.3.3-6: DETACH REQUEST (steps 42, 73, Table 22.5.4.3.2-1)

Derivation Path: TS 36.508 [18], Table 4.7.2-11

Information Element

Value/remark

Comment

Condition

Detach type

Type of detach

001

EPS detach

Switch off

1

"switch-off"

GUTI or IMSI

GUTI-2

Table 22.5.4.3.3-7: Message ATTACH REJECT (step 48, Table 22.5.4.3.2-1)

Derivation path: TS 36.508 [18], Table 4.7.2-3

Information Element

Value/Remark

Comment

Condition

Security header type

0000

"Plain NAS message, not security protected"

EMM cause

00000011

#3 "Illegal UE"

ESM message container

Not present

Table 22.5.4.3.3-8: Message ATTACH REJECT (step 79, Table 22.5.4.3.2-1)

Derivation path: TS 36.508 [18], Table 4.7.2-3

Information Element

Value/Remark

Comment

Condition

Security header type

0000

"Plain NAS message, not security protected"

EMM cause

00000101

#6 "Illegal ME"

ESM message container

Not present

Table 22.5.4.3.3-9: RRCConnectionRelease-NB (step 6, table 22.5.4.3.2-1)

Derivation Path: 36.508 table 8.1.6.1-9

Information Element

Value/remark

Comment

Condition

RRCConnectionRelease-NB ::= SEQUENCE {

rrc-TransactionIdentifier

RRC-TransactionIdentifier-DL

criticalExtensions CHOICE {

c1 CHOICE {

rrcConnectionRelease-r13 SEQUENCE {

releaseCause-r13

other

resumeIdentity-r13

Not present

extendedWaitTime-r13

25

redirectedCarrierInfo

Not present

lateNonCriticalExtension

Not present

nonCriticalExtension SEQUENCE {}

Not present

}

}

}

}

Table 22.5.4.3.3-10: Message ATTACH REQUEST (steps 47a1, 47b1, 78a1, 78b1, Table 22.5.4.3.2-1)

Derivation path: TS 36.508 [18], Table 4.7.2-4

Information Element

Value/remark

Comment

Condition

NAS key set identifier

TSC

‘0’B

native security context

NAS key set identifier

The value is the same value as per the registration which happened in steps 23-32b1

Old GUTI or IMSI

GUTI-2

Last visited registered TAI

TAI-3