7.1.11 Off-network / Group Call / Broadcast Group Call / Broadcast Group Call Retransmitting / Broadcast Group Call Release / Client Originated (CO)

36.579-23GPPMission Critical (MC) services over LTEPart 2: Mission Critical Push To Talk (MCPTT) User Equipment (UE) Protocol conformance specificationRelease 15TS

7.1.11.1 Test Purpose (TP)

(1)

with { UE (MCPTT Client) registered and authorised for MCPTT Service, including authorised to initiate broadcast calls in off-network environment, and the UE (MCPTT Client) is in an off-network environment }

ensure that {

when { the MCPTT User requests to initiate an MCPTT broadcast call }

then { UE (MCPTT Client) sends a GROUP CALL BROADCAST message and enters the "B2: in-progress broadcast group call" state }

}

(2)

with { UE (MCPTT Client) in the "B2: in-progress broadcast group call" state, and the UE (MCPTT Client) is in an off-network environment }

ensure that {

when { the timer TFB2 (broadcast retransmission) expires }

then { UE (MCPTT Client) retransmits the GROUP CALL BROADCAST message }

}

(3)

with { UE (MCPTT Client) in the "B2: in-progress broadcast group call" state, and the UE (MCPTT Client) is in an off-network environment }

ensure that {

when { the MCPTT User requests to end the MCPTT broadcast call }

then { UE (MCPTT Client) sends a GROUP CALL BROADCAST END message and enters the "B1: start-stop" state }

}

7.1.11.2 Conformance requirements

References: The conformance requirements covered in the current TC are specified in: TS 24.379 clauses 10.3.2.4.1, 10.3.2.4.9, 10.3.2.4.7, TS 24.380 clause 7.2.3.2.2. Unless otherwise stated these are Rel-13 requirements.

[TS 24.379, clause 10.3.2.4.1]

When in the "B1: start-stop" state, upon the indication from MCPTT user to initiate the broadcast group call, the MCPTT client:

1) shall generate an SDP body as specified in subclause 10.2.1.1.2 and store it as the SDP body of the call;

2) shall generate a random number with uniform distribution between 0 and 65535 and store it as the call identifier of the call;

3) shall store own MCPTT user ID as the originating MCPTT user ID of the call;

4) shall store "BROADCAST GROUP CALL" as the current call type;

5) shall generate a GROUP CALL BROADCAST message as specified in subclause 15.1.20. In the GROUP CALL BROADCAST message, the MCPTT client:

a) shall set the Call identifier IE to the stored call identifier of the call;

b) shall set the Call type IE to the stored current call type;

c) shall set the Originating MCPTT user ID IE to the stored originating MCPTT user ID of the call;

d) shall set the MCPTT group ID IE to the stored MCPTT group ID of the call; and

e) shall set the SDP IE to the stored SDP body of the call;

6) shall set the ProSe per-packet priority to the value corresponding to MCPTT off-network broadcast callas described in 3GPP TS 24.383 [45];

7) shall start floor control as originating floor participant as described specified in subclause 7.2 in 3GPP TS 24.380 [5];

8) shall send the GROUP CALL BROADCAST message as specified in subclause 10.2.1.1.1;

9) shall establish a media session based on the stored SDP body of the call;

10) shall start timer TFB2 (broadcast retransmission); and

11) shall enter the "B2: in-progress broadcast group call" state.

[TS 24.379, clause 10.3.2.4.9]

When in the "B2: in-progress broadcast group call" state, upon expiry of timer TFB2 (broadcast retransmission), the MCPTT client:

1) shall generate a GROUP CALL BROADCAST message as specified in subclause 15.1.20. In the GROUP CALL BROADCAST message, the MCPTT client:

a) shall set the Call identifier IE to the stored call identifier of the call;

b) shall set the Call type IE to the stored current call type;

c) shall set the Originating MCPTT user ID IE to the stored originating MCPTT user ID of the call;

d) shall set the MCPTT group ID IE to the stored MCPTT group ID of the call; and

e) shall set the SDP IE to the stored SDP body of the call;

2) shall send the GROUP CALL BROADCAST message as specified in subclause 10.2.1.1.1;

3) shall restart timer TFB2 (broadcast retransmission); and

4) shall remain in the "B2: in-progress broadcast group call" state.

[TS 24.379, clause 10.3.2.4.7]

When in the "B2: in-progress broadcast group call" state, upon an indication from the originating MCPTT user to release the in-progress broadcast group call, the MCPTT client:

1) shall release the media session;

2) shall generate a GROUP CALL BROADCAST END message as specified in subclause 15.1.21. In the GROUP CALL BROADCAST END message, the MCPTT client:

a) shall set the Call identifier IE to the stored call identifier of the call;

b) shall set the Originating MCPTT user ID IE to the stored originating MCPTT user ID of the call; and

c) shall set the MCPTT group ID IE to the stored MCPTT group ID of the call;

3) shall send the GROUP CALL BROADCAST END message as specified in subclause 10.2.1.1.1;

4) shall stop timer TFB2 (broadcast retransmission);

5) shall clear the stored call identifier;

6) shall stop floor control; and

7) shall enter the "B1: start-stop" state.

[TS 24.380, clause 7.2.3.2.2]

When an MCPTT call is established with session announcement including an explicit floor request, the originating floor participant:

1. shall create an instance of a floor participant state transition diagram for basic operation state machine;

2. shall send Floor Granted message towards other floor participants. The Floor Granted message:

a. shall include the granted priority in the Floor priority field;

b. shall include the MCPTT user’s own MCPTT ID in the User ID field; and

c. if the floor request is a broadcast group call, system call, emergency call or an imminent peril call, shall include a Floor Indicator field indicating the relevant call types;

3. shall set the stored SSRC of the current florr arbitrator to its own SSRC; and

4. shall enter ‘O: has permission’ state.

7.1.11.3 Test description

7.1.11.3.1 Pre-test conditions

System Simulator:

– SS-UE1 (MCPTT client)

– For the underlying "transport bearer" over which the SS and the UE will communicate, the SS is behaving as SS-UE1 as defined in TS 36.508 [24], configured for and operating as ProSe Direct Communication transmitting and receiving device.

– GNSS simulator to simulate a location and provide a timing reference for the assistance of E-UTRAN off-network testing.

NOTE 1: For operation in off-network environment, it needs be ensured that after the UE is powered up it considers the Geographical area #1 that is simulated by the GNSS simulator as being one of the geographical areas set in the USIM for operation when UE is "not served by E-UTRAN".

– SS-NW (MCPTT server)

– For the underlying "transport bearer" over which the SS and the UE will communicate Parameters are set to the default parameters for the basic E-UTRA Single cell network scenarios, as defined in TS 36.508 [24] clause 4.4. The simulated Cell 1 shall belong to PLMN1 (the PLMN specified for MCPTT operation in the MCPTT configuration document).

NOTE 2: The SS operation as NW (MCPTT server) is needed only for the Preamble if the UE has to perform the MCPTT User performs the Generic Test Procedure for MCPTT Authorization/Configuration and Key Generation as specified in TS 36.579-1 [2], subclause 5.3.2.

IUT:

– UE (MCPTT client)

– The test USIM set as defined in TS 36.579-1 [2], subclause 5.5.10 is inserted.

– For the underlying "transport bearer" over which the SS and the UE will communicate, the UE is behaving as a ProSe enabled UE as defined in TS 36.508 [24], configured for and operating as ProSe Direct Communication transmitting and receiving device.

Preamble:

– The UE has performed the Generic Test Procedure for MCPTT UE registration as specified in TS 36.579-1 [2], subclause 5.4.2.

– The MCPTT User performs the Generic Test Procedure for MCPTT Authorization/Configuration and Key Generation as specified in TS 36.579-1 [2], subclause 5.3.2.

– The GNSS simulator is configured to simulate a location in the centre of Geographical area #1 and provide a timing reference, as defined in TS 36.508 [24] Table 4.11.2-2 scenario #1.

– The UE is switched-off.

– UE States at the end of the preamble

– The UE is in state ‘switched-off’.

7.1.11.3.2 Test procedure sequence

Table 7.1.11.3.2-1: Main Behaviour

St

Procedure

Message Sequence

TP

Verdict

U – S

Message

1

Power up the UE

–

–

–

–

1A

Trigger the UE to reset UTC time and location.

NOTE: The UTC time and location reset may be performed by MMI or AT command (+CUTCR).

–

–

–

–

2

Activate the MCPTT Client Application and register User A as the MCPTT User (TS 36.579-5 [5], px_MCPTT_User_A_username, px_MCPTT_User_A_password).

(NOTE 1)

–

–

–

–

3

Make the UE (MCPTT Client) initiate an off-network broadcast call

(NOTE 1)

–

–

–

–

–

EXCEPTION: The E-UTRA/EPC actions which are related to the MCPTT off-network call establishment are described in TS 36.579-1 [2], subclause 5.4.11 ‘Generic Test Procedure for MCPTT CO communication over ProSe direct one-to-many communication out of E-UTRA coverage / Monitoring/Discoverer procedure for group member discovery / One-to-many communication’. The test sequence below shows only the MCPTT relevant messages exchanged.

–

–

–

–

4

Check: Does the UE (MCPTT client) send a GROUP CALL BROADCAST message?

(NOTE 2)

–>

GROUP CALL BROADCAST

1

P

4A

SS starts Timer=10s (Timer TFB2 (broadcast retransmission))

5

Check: Does the UE (MCPTT Client) send a Floor Granted message towards the other floor participants?

–>

Floor Granted

1

P

6

Timer=10s expires

–

–

–

–

7

Check: Does the UE (MCPTT client) send a GROUP CALL BROADCAST message using the same Call identifier IE as used in step 4?

–>

GROUP CALL BROADCAST

2

P

8

Make the UE (MCPTT Client) cancel the broadcast call

(NOTE 1), (NOTE 3)

–

–

–

–

9

Check: Does the UE (MCPTT client) send a GROUP CALL BROADCAST END message and enter the "B1: start-stop" state?

(NOTE 4)

–>

GROUP CALL BROADCAST END

3

P

NOTE 1: This is expected to be done via a suitable implementation dependent MMI.

NOTE 2: Timer TFB2 (broadcast retransmission) is started by the MCPTT Client upon the sending of the GROUP CALL BROADCAST message. Timer TFB2 (broadcast retransmission)=10s, as defined in TS 36.579-1 [2], Table 5.5.8.1-1. At the expire of timer TFB2 (broadcast retransmission), the MCPTT Client resends the GROUP CALL BROADCAST message.

NOTE 3: If the MCPTT User does not cancel the broadcast call before timer TFB2 (broadcast retransmission) expires, then the MCPTT Client will resend the GROUP CALL BROADCAST message per TS 24.379 [9] and the remaining steps will not be valid. If during test execution it is found that the specified timer value is not large enough, then a new value needs to be specified.

NOTE 4: Timer TFB2 (broadcast retransmission) is stopped by the MCPTT Client upon the sending of the GROUP CALL BROADCAST END message.

7.1.11.3.3 Specific message contents

Table 7.1.11.3.3-1: GROUP CALL BROADCAST (step 7, Table 7.1.11.3.2-1)

Derivation Path: TS 36.579-1 [2], Table 5.5.5.6.1-1

Information Element

Value/remark

Comment

Condition

Call identifier

Use the same Call identifier as used in the GROUP CALL BROADCAST message sent in step 3