U – S

Message/PDU/SDU

–

EXCEPTION: Unless otherwise stated all the messages below are transmitted on the cell specified in the test case.

–

–

–

–

1-3

Steps 1-3 from the mobility and periodic registration update procedure as described in Table 4.9.5.2.2-1 are performed.

For some consequences related to the content of the REGISTRATION REQUEST message sent in step 1 see the Notes in Table 4.9.9.2.3-1.

–

–

–

–

4

The SS transmits a DLInformationTransfer message and an AUTHENTICATION REQUEST message.

<–

NR RRC: DLInformationTransfer

5GMM: AUTHENTICATION REQUEST

–

–

5

The UE transmits an ULInformationTransfer message and an AUTHENTICATION RESPONSE message.

–>

NR RRC: ULInformationTransfer

5GMM: AUTHENTICATION RESPONSE

–

–

6

The SS transmits a DLInformationTransfer message and a SECURITY MODE COMMAND message.

<–

NR RRC: DLInformationTransfer

5GMM: SECURITY MODE COMMAND

–

–

7

The UE transmits an ULInformationTransfer message and a SECURITY MODE COMPLETE message.

–>

NR RRC: ULInformationTransfer

5GMM: SECURITY MODE COMPLETE

–

–

8

The SS transmits a SecurityModeCommand message.

<–

NR RRC: SecurityModeCommand

–

–

9

The UE transmits a SecurityModeComplete message.

–>

NR RRC: SecurityModeComplete

–

–

10-11

Steps 4-5 of Table 4.9.5.2.2-1 of the test procedure are performed.

–

–

–

–

12a1-13a1

Void

–

–

–

–

–

EXCEPTION: Steps 14a1 to 14b2b1 describe a step sequence depending on test case scenario; the "lower case letter" identifies a step sequence that take place if the test procedure is called in a particular scenario.

(NOTE 1)

–

–

–

–

14a1

IF Interworking without N26 interface supported THEN

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.

The UE may attempt to transfer some of the existing in S1 PDN connection(s) in which case in the PDU SESSION ESTABLISHMENT REQUEST message the request type shall be set to "existing PDU session" (NOTE 3).

–

–

–

–

–

EXCEPTION: Steps 14a2a1 to 14a2b1 describe a step sequence depending on test case scenario; the "lower case letter" identifies a step sequence that take place if the UE performs a specific action.

–

–

–

–

14a2a1

IF pc_noOf_PDUsNewConnection > 0 THEN the SS transmits an RRCRelease message to release RRC connection and moves the UE to RRC_IDLE.

<–

NR RRC: RRCRelease

–

–

14a2a2

The procedure NR RRC_IDLE Extension as specified in table 4.5.2.2-4 takes place.

–

–

–

–

14a2b1

ELSE IF connected without release is not present THEN, the SS transmits an RRCConnectionRelease message to release RRC connection and move the UE to RRC_IDLE.

<–

NR RRC: RRCRelease

–

–

–

EXCEPTION: In parallel to the events described in step 14b1 below, the steps specified in Table 4.9.9.2.2-2 may take place.

–

–

–

–

14b1

ELSE (i.e. ‘Interworking without N26 interface not supported’)

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 with the exception that IF step 2b1, Table 4.5A.2.2.2-2 takes place THEN the SS shall not assign Fail but continue with the next step in the test sequence not expecting any additional session establishment to take place (NOTE 2).

–

–

–

–

–

EXCEPTION: Steps 14b2a1 to 14b2b1 describe a step sequence depending on test case scenario; the "lower case letter" identifies a step sequence that take place if the UE performs a specific action.

–

–

–

–

14b2a1

IF pc_noOf_PDUsNewConnection> 0 THEN the SS transmits an RRCRelease message to release RRC connection and move the UE to RRC_IDLE.

<–

NR RRC: RRCRelease

–

–

14b2a2

The procedure NR RRC_IDLE Extension as specified in Table 4.5.2.2-4 takes place.

For the referred in step 8, Table 4.5.2.2-4, generic procedure for UE-requested PDU session establishment, specified in subclause 4.5A.2, IF step 2b1, Table 4.5A.2.2.2-2 takes place THEN the SS shall not assign Fail but continue with the next step in the test sequence not expecting any additional session establishment to take place (NOTE 2).

–

–

–

–

14b2b1

ELSE IF connected without release is not present THEN, the SS transmits an RRCRelease message to release RRC connection and move the UE to RRC_IDLE.

<–

NR RRC: RRCRelease

–

–

NOTE 1: The NWK will indicated whether Interworking without N26 interface is supported in the REGISTRATION ACCEPT message, IE ‘5GS network feature support’, IWK N26 bit. Consequently which branch would the procedure sequence go through will depend on the content of the REGISTRATION ACCEPT message applicable to e.g. the test case which calls the present test procedure.

NOTE 2: Depending on UE implementation and/or NWK behaviour, the UE may transfer some PDN connections into PDU sessions without re-establishing them with the relevant mapping provided in the ACTIVATE DEFAULT EPS BEARER CONTEXT REQUEST message. This will result in the number of connection modifications, if any, being lower than the pc_noOf_PDUsSameConnection or the pc_noOf_PDUsNewConnection which the UE will establish upon initial attach to the 5GS.

NOTE 3: Since the MME does not provide the UE with the mapped PDU session for a PDN connection, the UE does not know whether interworking to 5GS is supported for a PDN connection for which the UE assigned a PDU Session identity before attempting to transfer the PDN connection from S1 mode to N1 mode. It is up to UE implementation to decide which PDN connection(s) to be attempted to transfer from S1 mode to N1 mode, e.g. based on UE policy or UE local configuration. (see TS 24.501 [22], subclause 6.1.4.2)

U – S

Message

–

EXCEPTION: Step 1 describe a step sequence depending on test case scenario; the "lower case letter" identifies a step sequence that take place if the UE performs a specific action.

NOTE 2, NOTE 3

–

–

–

–

1

IF this is the first time in a test case that the UE moves from S1 to N1 THEN

the generic procedure for Procedure for UE-requested PDU session modification after the first S1 to N1 mode change / Single-registration mode with N26, specified in subclause 4.5A.2C, takes place with ExpectedNumberOfPDUSessionModifications=(pc_noOf_PDUsSameConnection+pc_noOf_PDUsNewConnection), with the exception that IF step 2b1, Table 4.5A.2C.2.2-2 takes place THEN the SS shall not assign Fail but continue with the next step in the test sequence not expecting any additional session modifications to take place (NOTE 1).

NOTE 1: Depending on UE implementation and/or NWK behaviour, the UE may transfer with modification some PDN connections into PDU sessions without re-establishing them with the relevant mapping provided in the ACTIVATE DEFAULT EPS BEARER CONTEXT REQUEST message. This will result in the number of session modifications, if any, being lower than the pc_noOf_PDUsSameConnection+pc_noOf_PDUsNewConnection.

NOTE 2: Whether this is the first time in a test case that the UE moves from S1 to N1 depends on the test scenario (including what happens in the preamble of the test).

NOTE 3: It is assumed that the PDU session modification for all transferred PDUs will happen on the same connection with the mobility and periodic registration update procedure.

NOTE 4: For PDN connections which will be transferred, tests calling the present procedure shall ensure that:
– For each PDN connection established during the UE registration to the EPS, the ACTIVATE DEFAULT EPS BEARER CONTEXT REQUEST message which corresponds to the default EPS bearer of the PDN connectivity being activated, contains the Protocol configuration options IE or the Extended protocol configuration options IE with mapped 5GS PDU a session-AMBR and QoS rule(s).

Information Element

Value/remark

Comment

Condition

5GS registration type

’00xxx010′

mobility registration updating

x – not checked

ngKSI

NAS key set identifier

KSI_AMF that was created when the UE last registered to 5GCN

Registered_Previously_on_5GCN

‘111’B

No key

Not_Registered_Previously_on_5GCN

TSC

‘0’B

native security context (for KSI_AMF)

Registered_Previously_on_5GCN

Not applicable

TSC does not apply for NAS key set identifier value "111"

Not_Registered_Previously_on_5GCN

5GS mobile identity

5G-GUTI mapped from the 4G-GUTI assigned when the UE last registered to EPC E-UTRA

Non-current native NAS key set identifier

Not present

5GMM capability

‘1’

S1 mode supported

Last visited registered TAI

The TAI the last visited NGC Cell belonged to, if any. Not included if the UE does not have last stored 5GC TAI.

S1 UE network capability

All octets with the exception of octet 8, bit 8 and octet 9, bit 6

Not checked

Extended protocol configuration options (ePCO) (octet 8, bit 8)

‘1’

Extended protocol configuration options IE supported

N1 mode supported (N1mode) (octet 9, bit 6)

‘1’

N1 mode supported

PDU session status

Any allowed value

(NOTE 1)

UE status

"UE is in EMM-REGISTERED state"

Additional GUTI

5G-GUTI assigned when the UE last registered to 5GC N

Registered_Previously_on_5GCN

Not present

Not_Registered_Previously_on_5GCN

EPS NAS message container

TRACKING AREA UPDATE REQUEST message

See Table 4.9.9.2.3-2

EPS bearer context status

Not present

(NOTE 2)

NOTE 1: The UE includes the PDU session status IE indicating the status of the PDU session(s) mapped during the inter-system change from S1 mode to N1 mode from the PDN connection(s) for which the EPS indicated that interworking to 5GS is supported, if any. This means that the UE has created locally the default bearer context and the dedicated bearer context(s) based on the parameters of the mapped bearer contexts or the associations between QoS flow and mapped bearer in the PDN connection. Although the contents of the IE is not required to be verified for PASS/FAIL purposes, the provided information shall be taken into account for building any subsequent RRC Reconfiguration message, and can be used e.g. for SS configuration purposes as well.

NOTE 2: The UE is assumed NOT to have locally deactivated EPS bearer context(s) for which interworking to 5GS is supported while the UE was in S1 mode without notifying the network.

Not_Registered_Previously_on_5GCN

UE has not_registered_previously_on_5GCN. UE does not have valid 5G NAS security context and 5G-GUTI.

Registered_Previously_on_5GCN

UE has registered_previously_on_5GCN. UE have valid 5G NAS security context and 5G-GUTI

Information Element

Value/remark

Comment

Condition

EPS update type

EPS update type Value

‘000’B

TA updating

"Active" flag

‘0’B

No Bearer Establishment requested

NAS key set identifier

the eKSI for the current EPS security context

TSC

‘0’B

‘1’B

Mapped EPS security context

Old GUTI

4G-GUTI assigned when the UE last registered to EPC E-UTRA

UE network capability

Not present

Last visited registered TAI

Not present

DRX parameter

Not present

UE radio capability information update needed

Not present

EPS bearer context status

Not present

MS network capability

Not present

Old location area identification

Not present

TMSI status

Not present

Mobile station classmark 2

Not present

Mobile station classmark 3

Not present

Supported Codecs

Not present

Additional update type

Not present

Voice domain preference and UE’s usage setting

Not present

Old GUTI type

Not present

Device properties

Not present

MS network feature support

Not present

TMSI based NRI container

Not present

T3324 value

Not present

T3412 extended value

Not present

Extended DRX parameters

Not present

UE additional security capability

Not present

UE status

Not present

Additional information requested

Not present

NOTE: The message shall be integrity protected using the current EPS security context.

Mapped EPS security context

When explicitly specified by the test case in which the message is used.

Information Element

Value/remark

Comment

Condition

5GS network feature support

The IWK N26 (octet 4, bit 7) set to ‘1’

Interworking without N26 interface supported