11.2.4 Emergency bearer services / Normal cell / NO-IMSI / Attach / No EPS security context / PDN connect / Service request / Timer T3412 expires

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

11.2.4.1 Test Purpose (TP)

(1)

with { UE is switched-on without a valid USIM inserted }

ensure that {

when { the UE was triggered to originate an emergency bearer service }

then { the UE establishes the RRC connection with the RRC establishmentCause set to "emergency call" }

}

(2)

with { UE is switched-on without a valid USIM inserted, and has originated an emergency bearer service }

ensure that {

when { the UE receives an RRCConnectionSetup message }

then { the UE sends an ATTACH REQUEST message with the EPS attach type set to " EPS emergency attach" }

}

(3)

with { UE without a valid USIM inserted has sent an ATTACH REQUEST message for emergency bearer service }

ensure that {

when { The UE receives an ATTACH ACCEPT message }

then { The UE sends an ATTACH COMPLETE message }

}

(4)

void

(5)

with { UE without a valid USIM inserted has completed Emergency service and enters EMM-IDLE MODE }

ensure that {

when { the periodic tracking area updating timer T3412 expires }

then { UE does not send an TRACKING AREA UPDATE REQUEST message }

}

(6)

with { UE without a valid USIM inserted }

ensure that {

when { the user dials one of the numbers 112, 911, 000, 08, 110, 999, 118 and 119 }

then { UE recognises them as emergency numbers and initiates an emergency call thereby confirming that the numbers are permanently stored on the ME as emergency numbers }

}

11.2.4.2 Conformance requirements

References: The conformance requirements covered in the current TC are specified in: TS 24.301, clauses 5.2.2.3.5, 5.3.1.1, 5.3.5, 5.4.2.1, 5.5.1.2.1, 5.5.1.2.2, 5.5.1.2.3, 6.4.1.3 and Annex D, and, TS 22.101 clause 10.1.1 Unless otherwise stated these are Rel-9 requirements..

[TS 24.301, clause 5.2.2.3.5]

The UE shall perform cell selection according to 3GPP TS 36.304 [21].

The UE may initiate attach for emergency bearer services.

[TS 24.301, clause 5.3.1.1]

When the UE is in EMM-IDLE mode and needs to transmit an initial NAS message, the UE shall request the lower layer to establish a RRC connection. In this request to the lower layer the NAS shall provide to the lower layer the RRC establishment cause and the call type as specified in annex D of this specification.

…

For the routing of the initial NAS message to the appropriate MME, the UE NAS provides the lower layers with either the S-TMSI or the registered globally unique MME identifier (GUMMEI) that consists of the PLMN ID, the MME group ID, and the MME code (see 3GPP TS 23.003 [2]) according to the following rules:

– When the UE is registered in the tracking area of the current cell during the NAS signalling connection establishment, the UE NAS shall provide the lower layers with the S-TMSI, but shall not provide the registered MME identifier to the lower layers. Exceptionally, when the UE in EMM-IDLE mode initiates a tracking area updating or combined tracking area updating procedure for load balancing purposes, the UE NAS shall provide the lower layers with neither S-TMSI nor registered MME identifier.

– When the UE is not registered in the tracking area of the current cell during the NAS signalling connection establishment, the UE NAS does not provide the lower layers with the S-TMSI. Instead,

a) if the TIN indicates "GUTI" or "RAT-related TMSI", or the TIN is not available, and the UE holds a valid GUTI, the UE NAS shall provide the lower layers with the MME identifier part of the valid GUTI; or

b) if the TIN indicates "P-TMSI" and the UE holds a valid P-TMSI and RAI, the UE NAS shall provide the lower layers with the MME identifier part of the mapped GUTI, which is generated from the P-TMSI and RAI.

[TS24.301 clause5.3.5]

Periodic tracking area updating is used to periodically notify the availability of the UE to the network. The procedure is controlled in the UE by the periodic tracking area update timer (timer T3412). The value of timer T3412 is sent by the network to the UE in the ATTACH ACCEPT message and can be sent in the TRACKING AREA UPDATE ACCEPT message. The UE shall apply this value in all tracking areas of the list of tracking areas assigned to the UE, until a new value is received.

The timer T3412 is reset and started with its initial value, when the UE goes from EMM-CONNECTED to EMM-IDLE mode. The timer T3412 is stopped when the UE enters EMM-CONNECTED mode or EMM-DEREGISTERED state.

If the UE is attached for emergency bearer services, and timer T3412 expires, the UE shall not initiate a periodic tracking area updating procedure, but shall locally detach from the network.

When a UE is not attached for emergency bearer services, and timer T3412 expires, the periodic tracking area updating procedure shall be started and the timer shall be set to its initial value for the next start.

…

If the UE is not attached for emergency bearer services, the mobile reachable timer shall be longer than T3412.In this case, by default, the mobile reachable timer is 4 minutes greater than T3412. If ISR is not activated, the network behaviour upon expiry of the mobile reachable timer is network dependent, but typically the network stops sending paging messages to the UE on the first expiry, and may take other appropriate actions.

If the UE is attached for emergency bearer services, the MME shall set the mobile reachable timer with a value equal toT3412. When the mobile reachable timer expires, the MME shall locally detach the UE.

[TS 24.301, clause 5.4.2.1]

The purpose of the EPS authentication and key agreement (AKA) procedure is to provide mutual authentication between the user and the network and to agree on a key KASME (see 3GPP TS 33.401 [19]). The cases when the EPS AKA procedure should be used are defined in 3GPP TS 33.401 [19].

The EPS AKA procedure is always initiated and controlled by the network. However, the UE can reject the EPS authentication challenge sent by the network.

The UE shall proceed with an EPS authentication challenge only if a USIM is present.

[TS 24.301, clause 5.5.1.1]

The attach procedure is used to attach to an EPC for packet services in EPS.x

The attach procedure is used for three purposes:

– by a UE in PS mode of operation to attach for EPS services only;

– by a UE in CS/PS mode 1 or CS/PS mode 2 of operation to attach for both EPS and non-EPS services; or

– to attach for emergency bearer services.

If the MME does not support an attach for emergency bearer services, the MME shall reject any request to attach with an attach type set to "EPS emergency attach".

With a successful attach procedure, a context is established for the UE in the MME, and a default bearer is established between the UE and the PDN GW, thus enabling always-on IP connectivity to the UE. The network may also initiate the activation of dedicated bearers as part of the attach procedure.

[TS 24.301, clause 5.5.1.2.1]

When the UE initiates the attach procedure for emergency bearer services, the UE shall indicate "EPS emergency attach" in the EPS attach type IE.

[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.

If the UE supports neither A/Gb mode nor Iu mode, the UE shall handle the Old GUTI or IMSI IE in the ATTACH REQUEST message as follows:

– The UE shall include in the ATTACH REQUEST message a valid GUTI together with the last visited registered TAI, if available. If there is no valid GUTI available, the UE shall include the IMSI in the ATTACH REQUEST message.

If the UE is attaching for emergency bearer services and does not hold a valid GUTI, P-TMSI or IMSI as described above, the IMEI shall be included in the EPS mobile identity IE.

…

The UE shall send the ATTACH REQUEST message together with a PDN CONNECTIVITY REQUEST message contained in the ESM message container information element to request PDN connectivity.

…

If a valid NAS security context exists, the UE shall integrity protect the ATTACH REQUEST message combined with the PDN CONNECTIVITY REQUEST message. When the UE does not have a valid NAS security context, the ATTACH REQUEST message combined with the PDN CONNECTIVITY REQUEST message is not integrity protected.

[TS 24.301, clause 5.5.1.2.3]

During an attach for emergency bearer services, the MME may choose to skip the authentication procedure even if no EPS security context is available and proceed directly to the execution of the security mode control procedure as specified in subclause 5.4.3.

[TS 24.301, clause 6.4.1.3]

Upon receipt of the ACTIVATE DEFAULT EPS BEARER CONTEXT REQUEST message, the UE shall send an ACTIVATE DEFAULT EPS BEARER CONTEXT ACCEPT message and enter the state BEARER CONTEXT ACTIVE. When the default bearer is activated as part of the attach procedure, the UE shall send the ACTIVATE DEFAULT EPS BEARER CONTEXT ACCEPT message together with ATTACH COMPLETE message. When the default bearer is activated as the response to the stand-alone PDN CONNECTIVITY REQUEST message, the UE shall send the ACTIVATE DEFAULT EPS BEARER CONTEXT ACCEPT message alone.

The UE checks the PTI in the ACTIVATE DEFAULT EPS BEARER CONTEXT REQUEST message to identify the UE requested PDN connectivity procedure to which the default bearer context activation is related (see subclause 6.5.1).

[TS 24.301, Annex D]

Table D.1.1: Mapping of NAS procedure to establishment cause and call type

NAS procedure

RRC establishment cause (according 3GPP TS 36.331 [22])

Call type

Attach

If an ATTACH REQUEST has EPS attach type not set to "EPS emergency attach", the RRC establishment cause shall be set to MO signalling. (See Note 1)

"originating signalling"

If an ATTACH REQUEST has EPS attach type set to "EPS emergency attach", the RRC establishment cause shall be set to Emergency call. (See Note 1)

"emergency calls"

Note 1: For these NAS procedures initiated by UEs of access class 12, 13 or 14 in their home country, the RRC establishment cause will be set to "High priority access AC 11 – 15". For this purpose the home country is defined as the country of the MCC part of the IMSI, see 3GPP TS 22.011 [1A].
For these NAS procedures initiated by UE of access class 11 or 15 in their HPLMN (if the EHPLMN list is not present or is empty) or EHPLMN (if the EHPLMN list is present), the RRC establishment cause will be set to "High priority access AC 11 – 15".

[TS 22.101 clause 10.1.1]

The ME shall identify an emergency number dialled by the end user as a valid emergency number and initiate emergency call establishment if it occurs under one or more of the following conditions. If it occurs outside of the following conditions, the ME should not initiate emergency call establishment but normal call establishment. Emergency number identification takes place before and takes precedence over any other (e.g. supplementary service related) number analysis.

a) 112 and 911 shall always be available. These numbers shall be stored on the ME.

b) Any emergency call number stored on a SIM/USIM when the SIM/USIM is present.

c) 000, 08, 110, 999, 118 and 119 when a SIM/USIM is not present. These numbers shall be stored on the ME.

11.2.4.3 Test description

11.2.4.3.1 Pre-test conditions

System Simulator:

– Cell A is configured according to Table 6.3.2.2-1 in [18].

UE:

  • Without a valid USIM inserted

Preamble:

– The UE is in state Switched OFF (state 1) according to [18].

11.2.4.3.2 Test procedure sequence

Table: 11.2.4.3.2-1: Main behaviour

St

Procedure

Message Sequence

TP

Verdict

U – S

Message

1

The UE is switched on.

–

–

–

–

2

Cause the UE to originate an emergency bearer service (Note1) by dialling 112.

–

–

–

–

3

Check: Does the UE transmit an RRCConnectionRequest message with establishmentCause set to ‘Emergency call’?

–

RRCConnectionRequest

1

P

4

The SS transmits an RRCConnectionSetup message.

–

RRCConnectionSetup

–

–

5

Check: Does the UE transmit an ATTACH REQUEST message to attach for emergency bearer services, together with a PDN CONNECTIVITY REQUEST message for emergency bearer services?

–>

ATTACH REQUEST

PDN CONNECTIVITY REQUEST

2

P

6-14

Steps 5a1 to 15 of the generic test procedure for IMS Emergency call establishment in EUTRA: Limited Service (TS 36.508 subclause 4.5A.5.3-1).

–

–

–

–

15-16

Void

–

–

–

–

17

Check: Does the UE transmit an ATTACH COMPLETE message, and the ACTIVATE DEFAULT EPS BEARER CONTEXT ACCEPT message is piggybacked in ATTACH COMPLETE?

–>

ATTACH COMPLETE

ACTIVATE DEFAULT EPS BEARER CONTEXT ACCEPT

3

P

18-20

Steps17 to 19 of the generic test procedure for IMS Emergency call establishment in EUTRA: Limited Service (TS 36.508 subclause 4.5A.5.3-1).

–

–

–

–

20AA

The SS waits 1 second.

–

–

–

–

20A

Release IMS Call (see Note 2)

–

–

–

–

20Ba1

Void

–

–

–

–

20Ba2

Void

–

–

–

–

20Bb1

Void

–

–

–

–

20Bb2

Void

–

–

–

–

21

Void

–

–

–

–

21A

The SS releases the RRC connection

–

–

–

–

22

The SS waits 6minutes. (Expiry of T3412)

–

–

–

–

23

Check: Does the UE send TRACKING AREA UPDATE REQUEST message?

–>

TRACKING AREA UPDATE REQUEST

5

F

–

EXCEPTION: Steps 24 to 45 are repeated for all of the dialling numbers in the set {911, 000, 08, 110, 999, 118, 119} every time using a different dialling number.

–

–

–

–

24

Cause the UE to start a "call" using one of the Numbers listed in the EXCEPTION step above.

–

–

–

–

25

Check: Does UE transmit an RRCConnectionRequest message with establishmentCause set to ‘emergency"?

–>

RRCConnectionRequest

6

P

26-42

Steps 3 to 19 of the generic test procedure for IMS Emergency call establishment in EUTRA: Limited Service (TS 36.508 subclause 4.5A.5.3-1).

–

–

–

–

43

The SS waits 1 second.

–

–

–

–

44

Release IMS Call (see Note 2).

–

–

–

–

44Aa1

Void

–

–

–

–

44Aa2

Void

–

–

–

–

44Ab1

Void

–

–

–

–

44Ab2

Void

–

–

–

–

44B

The SS transmits a DETACH REQUEST message with the Detach type IE indicating “re-attach required” to regain normal service.

<–

DETACH REQUEST

–

–

44C

The UE responds the DETACH ACCEPT message.

–>

DETACH ACCEPT

–

–

45

The SS releases the RRC connection.

–

–

–

–

Note 1: The request to originate a emergency service may be performed by MMI or AT command.

Note 2: The IMS Call is released using the generic procedure in TS 34.229-1 [35] subclause C.32.

11.2.4.3.3 Specific message contents

Table 11.2.4.3.3-1: Message RRCConnectionRequest (step 3, Table 11.2.4.3.2-1)

Derivation path: 36.508 table 4.6.1-16

Information Element

Value/Remark

Comment

Condition

RRCConnectionRequest ::= SEQUENCE {

criticalExtensions CHOICE {

rrcConnectionRequest-r8 SEQUENCE {

ue-Identity CHOICE {

randomValue

Not checked

}

establishmentCause

Emergency call

}

}

}

Table 11.2.4.3.3-2: Message ATTACH REQUEST (step 5, Table 11.2.4.3.2-1)

Derivation path: TS 36.508 table 4.7.2-4

Information Element

Value/Remark

Comment

Condition

EPS attach type

‘0110’B

EPS emergency attach

EPS mobile identity

IMEI

Table 11.2.4.3.3-3: Message ATTACH ACCEPT (step 14, 36.508, Table 4.5A.5.3-11)

Derivation path: 36.508 table 4.7.2-1

Information Element

Value/Remark

Comment

Condition

T3412 value

Unit

‘010’

”value is incremented in multiples of decihours”

Timer value

‘00001’

”6 minutes”

Table 11.2.4.3.3-4: Void

Table 11.2.4.3.3-5: DETACH REQUEST (Step 44B Table 11.2.4.3.2-1)

Derivation Path: 36.508 table 4.7.2-11

Information Element

Value/remark

Comment

Condition

Detach type

Type of detach

001

re-attach required

Switch off

0

normal detach