17.4.8 Continued MBMS service reception after E-UTRAN release of unicast bearer

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

17.4.8.1 Test Purpose (TP)

(1)

with { UE in RRC Connected state on a MBMS cell and is prioritising MBMS service over unicast data }

ensure that {

when { UE receives the SystemInformationBlockType15 message broadcasted on the MBMS cell }

then { UE transmits a MBMSInterestIndication message including the mbms-Priority IE indicating that UE prioritises reception of MBMS frequencies above reception of any of the unicast bearers }

}

(2)

with { UE in E-UTRA RRC_Connected state with a unicast bearer configured AND is receiving MBMS service }

ensure that {

when { UE receives a RRCConnectionReconfiguration message to release the unicast bearer }

then { UE accepts the release of the unicast bearer and continues to receive MBMS service }

}

17.4.8.2 Conformance requirements

References: The conformance requirements covered in the present TC are specified in: TS 36.331 clause 5.8.5.4. Unless otherwise stated these are Rel-11 requirements.

[TS 36.331 clause 5.8.5.4]

The UE shall set the contents of the MBMSInterestIndication message as follows:

1> if the set of MBMS frequencies of interest, determined in accordance with 5.8.5.3, is not empty:

2> include mbms-FreqList and set it to include the MBMS frequencies of interest, using the EARFCN corresponding with freqBandIndicator included in SystemInformationBlockType1, if applicable, and the EARFCN(s) as included in SystemInformationBlockType15;

NOTE 1: The mbms-FreqList merely indicates the physical frequencies the UE is interested to receive and does not imply the UE supports the associated band.

2> include mbms-Priority if the UE prioritises reception of all indicated MBMS frequencies above reception of any of the unicast bearers;

NOTE 2: If the UE prioritises MBMS reception and unicast data cannot be supported because of congestion on the MBMS carrier(s), E-UTRAN may initiate release of unicast bearers. It is up to E-UTRAN implementation whether all bearers or only GBR bearers are released. E-UTRAN does not initiate re-establishment of the released unicast bearers upon alleviation of the congestion.

The UE shall submit the MBMSInterestIndication message to lower layers for transmission.

17.4.8.3 Test description

17.4.8.3.1 Pre-test conditions

System Simulator:

  • Cell 1 "Serving cell", as defined in TS 36.508 Table 6.2.2.1-1.
  • MBSFNAreaConfiguration message as defined in TS 36.508 [18] Table 4.6.1-4A is transmitted on Cell 1.

– System information combination 15 as defined in TS 36.508[18] clause 4.4.3.1 is used in E-UTRA Cell 1.

UE:

– The UE is configured to receive MBMS services.

Preamble:

– UE is in state Loopback Activated (State 4) with UE TEST LOOP MODE C on Cell 1 according to [18].

– The UE has one dedicated EPS bearer (DRB2) established.

– The UE is made interested in receiving MBMS service with MBMS Service ID=0 in the PLMN associated with the MBMS SAI (1) broadcasted in SIB15 on Cell 1.

– The UE is configured to prioritise reception of MBMS frequencies above reception of any unicast bearers.

– The UE is made aware that the MBMS service is active.

17.4.8.3.2 Test procedure sequence

Table 17.4.8.3.2-1: Main behaviour

St

Procedure

Message Sequence

TP

Verdict

U – S

Message

1

The SS transmits a Paging message including a systemInfoModification for cell1.

<–

Paging

–

–

–

EXCEPTION: the behaviour in table 17.4.8.3.2-2 runs in parallel with steps 3 to 7 below.

–

–

–

–

2

From the beginning of the next modification period the SS transmits SystemInformationBlockType15 according to system information combination 19 as defined in TS 36.508[18] clause 4.4.3.1 including mbms-SAI-IntraFreq-r11 list indicating MBMS SAI=1.

<–

SystemInformationBlockType15

–

–

3

UE transmits MBMSInterestIndication message.

–>

MBMSInterestIndication

–

–

4

Wait for a period equal to the MCCH repetition period for the UE to receive MBSFNAreaConfiguration message.

–

–

–

–

5

Void

–

–

–

–

–

Exception; Step 6 is repeated 5 times

–

–

–

–

6

The SS transmits 2 MBMS Packets on the MTCH in the next MCH Scheduling Period, with MCH Scheduling Information MAC Control Element with LCID=’00001’, Stop MTCH= ‘00000000001’ in the first MAC PDU of the MCH Scheduling Period.

<–

MBMS Packets

–

–

7

Void

–

-.

–

–

8

The SS transmits an UE TEST LOOP MODE C MBMS PACKET COUNTER REQUEST message.

<–

UE TEST LOOP MODE C MBMS PACKET COUNTER REQUEST

–

–

9

UE responds with UE TEST LOOP MODE C MBMS PACKET COUNTER RESPONSE.

–>

UE TEST LOOP MODE C MBMS PACKET COUNTER RESPONSE

–

–

10

Check: Is the number of reported MBMS Packets received on the MTCH in step 9 greater than zero?

–

–

2

P

11

The SS transmits an RRCConnectionReconfiguration message to release the unicast bearer (DRB2 that established during preamble) due to congestion on the MBMS carrier(s)

<–

RRCConnectionReconfiguration

–

–

12

The UE transmits an RRCConnectionReconfigurationComplete message to confirm the release.

–>

RRCConnectionReconfigurationComplete

–

–

–

Exception; Step 13 is repeated 5 times

–

–

–

–

13

The SS transmits 2 MBMS Packets on the MTCH in the next MCH Scheduling Period, with MCH Scheduling Information MAC Control Element with LCID=’00001’, Stop MTCH= ‘00000000001’ in the first MAC PDU of the MCH Scheduling Period.

<–

MBMS Packets

–

–

14

Void

–

–

–

–

15

The SS transmits an UE TEST LOOP MODE C MBMS PACKET COUNTER REQUEST message.

<–

UE TEST LOOP MODE C MBMS PACKET COUNTER REQUEST

–

–

16

UE responds with UE TEST LOOP MODE C MBMS PACKET COUNTER RESPONSE.

–>

UE TEST LOOP MODE C MBMS PACKET COUNTER RESPONSE

–

–

17

Check: Does the number of reported MBMS Packets received on the MTCH is greater than the number of MBMS Packets reported in step10?

–

–

2

P

Table 17.4.8.3.2-2: Parallel behaviour

St

Procedure

Message Sequence

TP

Verdict

U – S

Message

1

Check: Does UE transmit a MBMSInterestIndication message including the mbms-Priority IE set to True?

–>

MBMSInterestIndication

1

P

17.4.8.3.3 Specific message contents

Table 17.4.8.3.3-1: SystemInformationBlockType2 for Cells 1 (Preamble and all steps, Table 17.4.8.3.2-1)

Derivation Path: 36.508 table 4.4.3.3-1, condition MBMS.

Table 17.4.8.3.3-2: RRCConnectionReconfiguration (step 11, Table 17.4.8.3.2-1)

Derivation Path: 36.508, Table 4.6.1-8, condition DRB-REL

Table 17.4.8.3.3-3: MBMSInterestIndication (step 1, Table 17.4.8.3.2-2)

Derivation Path: 36.508, Table 4.6.1-4C

Information Element

Value/remark

Comment

Condition

criticalExtensions CHOICE {

c1 CHOICE{

interestIndication-r11 OF SEQUENCE {

mbms-Priority-r11

true

ENUMERATED {true}

}

}

}