7.3.7 PDCP Dual Connectivity

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

Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM

7.3.7.1 PDCP Uplink Routing / Split DRB

7.3.7.1.1 Test Purpose (TP)

(1)

with { UE in connected mode with SCG activated with a Split DRB established and with ul-DataSplitDRB-ViaSCG set to TRUE }

ensure that {

when { UE has PDCP SDUs available for transmission }

then { the UE transmits the PDCP SDUs on the MAC entity configured for SCG }

}

(2)

with { UE in connected mode with SCG activated with a Split DRB established and with ul-DataSplitDRB-ViaSCG set to FALSE }

ensure that {

when { UE has PDCP SDUs available for transmission }

then { the UE transmits the PDCP SDUs on the MAC entity configured for MCG }

}

7.3.7.1.2 Conformance requirements

References: The conformance requirements covered in the present TC are specified in: 3GPP TS 36.323 clause 4.2.2.

[TS 36.323, clause 4.2.2]

For split bearers, routing is performed in the transmitting PDCP entity, and reordering is performed in the receiving PDCP entity. When submitting PDCP PDUs to lower layers, the transmitting PDCP entity shall:

– if ul-DataSplitDRB-ViaSCG is set to TRUE by upper layers [3]:

– submit the PDCP PDUs to the associated AM RLC entity configured for SCG;

– else:

– submit the PDCP PDUs to the associated AM RLC entity configured for MCG.

7.3.7.1.3 Test description

7.3.7.1.3.1 Pre-test conditions

System Simulator:

– Cell 1 is the PCell, and Cell 10 is the PSCell.

– System information combination 3 as defined in TS 36.508 [18] clause 4.4.3.1 is used in E-UTRA Cell 1 and Cell 10.

UE:

None.

Preamble

– The UE is in state DC Split DRB Loopback Activated (state 6B) on Cell 1 and Cell 10 according to [18].

7.3.7.1.3.2 Test procedure sequence

Table 7.3.7.1.3.2-1: Main behaviour

St	Procedure	Message Sequence		TP	Verdict
		U – S	Message
1	The SS sends a PDCP Data PDU on the split DRB on Cell 1 (PCell).	<–	PDCP DATA PDU
2	Check: Does UE transmit a PDCP Data PDU on the AM RLC entity configured for SCG on Cell 10 (PSCell)	–>	PDCP DATA PDU	1	P
3	The SS reconfigure the split DRB to transmit uplink data on the AM RLC entity configured for SCG by sending a RRCConnectionReconfiguration on Cell 1 (PCell) message with IE ul-DataSplitDRB-ViaSCG set to FALSE.	<–	RRCConnectionReconfiguration	–	–
4	The UE transmits a RRCConnectionReconfigurationComplete message on Cell 1 (PCell).	–>	RRCConnectionReconfigurationComplete	–	–
5	The SS sends a PDCP Data PDU on the split DRB on Cell 1 (PCell).	<–	PDCP DATA PDU
6	Check: Does UE transmit a PDCP Data PDU on the AM RLC entity configured for MCG of the split DRB on Cell 1 (PCell)	–>	PDCP DATA PDU	2	P

7.3.7.1.3.3 Specific message contents

Table 7.3.7.1.3.3-1: RRCConnectionReconfiguration (Step 3, Table 7.3.7.1.3.2-1)

Derivation Path: 36.508, Table 4.6.1-8, condition PSCell_Add_Split_DRB

Table 7.3.7.1.3.3-2: PDCP-Config-DRB-AM (Table 7.3.7.1.3.3-1)

Derivation Path: 36.508, Table 4.8.2.1.2.2-1
Information Element	Value/remark	Comment	Condition
PDCP-Config-DRB-AM ::= SEQUENCE {
ul-DataSplitDRB-ViaSCG-r12	FALSE	Uplink transmission of split DRB PDCP SDUs configured to be transmitted on the PCell
}

7.3.7.2 PDCP Data Recovery / Reconfiguration of Split DRB

7.3.7.2.1 Test Purpose (TP)

(1)

with { UE in connected mode with SCG activated with a Split DRB established using RLC-AM }

ensure that {

when { network requests reconfiguration of the Split DRB (without handover)}

then { UE reconfigures the Split DRB and performs retransmission of all the PDCP PDUs previously submitted to re-established AM RLC entity in ascending order of the associated COUNT values from the first PDCP PDU for which the successful delivery has not been confirmed by lower layers }

}

7.3.7.2.2 Conformance requirements

References: The conformance requirements covered in the present TC are specified in: 3GPP TS 36.323 clause 5.9 and TS 36.331, clause 5.3.10.10.

[TS 36.323, clause 5.9]

When upper layers request a PDCP Data Recovery for a radio bearer, the UE shall:

– if the radio bearer is configured by upper layers to send a PDCP status report in the uplink (statusReportRequired [3]), compile a status report as described in subclause 5.3.1, and submit it to lower layers as the first PDCP PDU for the transmission;

– perform retransmission of all the PDCP PDUs previously submitted to re-established AM RLC entity in ascending order of the associated COUNT values from the first PDCP PDU for which the successful delivery has not been confirmed by lower layers.

After performing the above procedures, the UE shall follow the procedures in subclause 5.1.1.

[TS 36.331, clause 5.3.10.10]

The UE shall:

1> if the received scg-Configuration is set to release or includes the mobilityControlInfoSCG (i.e. SCG release/ change):

2> if mobilityControlInfo is not received (i.e. SCG release/ change without HO):

3> reset SCG MAC, if configured;

3> for each drb-Identity value that is part of the current UE configuration:

4> if the DRB indicated by drb-Identity is an SCG DRB:

5> re-establish the PDCP entity and the SCG RLC entity or entities;

4> if the DRB indicated by drb-Identity is a split DRB:

5> perform PDCP data recovery and re-establish the SCG RLC entity;

…

7.3.7.2.3 Test description

7.3.7.2.3.1 Pre-test conditions

System Simulator:

– Cell 1 is the PCell, and Cell 10 is the PSCell.

– System information combination 3 as defined in TS 36.508 [18] clause 4.4.3.1 is used in E-UTRA Cell 1 and Cell 10.

UE:

None.

Preamble

– The UE is in state DC Split DRB Loopback Activated (state 6B) on Cell 1 and Cell 10 according to [18].

7.3.7.2.3.2 Test procedure sequence

Table 7.3.7.2.3.2-1: Main behaviour

St	Procedure	Message Sequence		TP	Verdict
		U – S	Message
1	The SS is configured on Cell 10 (PSCell) not to send RLC acknowledgements (RLC ACKs) to the UE.
2	The SS creates 3 PDCP Data PDUs and the Next_PDCP_TX_SN is set to "0".	–	–	–	–
–	EXCEPTION: Step 3 and 4 shall be repeated for k=0 to 2 (increment=1).	–	–	–	–
3	The SS sends the PDCP Data PDU #k on the split DRB on Cell 1 (PCell): D/C field = 1 (PDCP Data PDU) and PDCP SN = k. After having sent a PDU, the SS sets Next_PDCP_TX_SN= k+1.	<–	PDCP PDU DATA #k	–	–
4	The UE sends the PDCP Data PDU #k on the AM RLC entity configured for SCG on Cell 10 (PSCell): D/C field = 1 (PDCP Data PDU) and PDCP SN = k. Data is previously received data from PDU #k.	–>	PDCP PDU DATA #k	–	–
5	The SS reconfigures the split DRB to transmit uplink data on the AM RLC entity configured for SCG by sending a RRCConnectionReconfiguration message on Cell 1 (PCell) with mobilityControlInfoSCG and reconfiguration of the split DRB.	<–	RRCConnectionReconfiguration	–	–
6	The UE transmits a RRCConnectionReconfigurationComplete message on Cell 1 (PCell).	–>	RRCConnectionReconfigurationComplete	–	–
7	The UE sends a PDCP Control PDU on the AM RLC entity configured for SCG on Cell 10 (PSCell), with the following content to the SS: D/C field = 0 (PDCP control PDU) and PDU Type =000, FMS field = 3.	–>	PDCP STATUS REPORT	–	–
–	EXCEPTION: Step 8 shall be repeated for k=0 to 2(increment=1).
8	Check: Does the UE send the PDCP Data PDU #k via on the AM RLC entity configured for SCG on Cell 10 (PSCell): D/C field = 1 (PDCP Data PDU) and PDCP SN = k. Data is previously received data from PDU #k ?	–>	PDCP DATA PDU #k	1	P

7.3.7.2.3.3 Specific message contents

Table 7.3.7.2.3.3-1: RRCConnectionReconfiguration (Step 5, Table 7.3.7.2.3.2-1)

Derivation Path: 36.508, Table 4.6.1-8, condition PSCell_Add_Split_DRB
Information Element	Value/remark	Comment	Condition
RRCConnectionReconfiguration ::= SEQUENCE {}
criticalExtensions CHOICE {
c1 CHOICE{
rrcConnectionReconfiguration-r8 SEQUENCE {
nonCriticalExtension SEQUENCE {		v890
nonCriticalExtension SEQUENCE {		v920
nonCriticalExtension SEQUENCE {		v1020
nonCriticalExtension SEQUENCE {		v1130
nonCriticalExtension SEQUENCE {		v1250
scg-Configuration-r12 CHOICE {	SCG-Configuration-r12-Mobility
}
}
}
}
}
}
}
}
}

Table 7.3.7.2.3.3-2: SCG-Configuration-r12-Mobility (Table 7.3.7.2.3.3-1)

Derivation Path: 36.508 Table 4.6.3-19F with condition PSCell_Add_Split_DRB
Information Element	Value/remark	Comment	Condition
scg-Configuration-r12 CHOICE {
setup SEQUENCE {
scg-ConfigPartMCG-r12	Not present
scg-ConfigPartSCG-r12 SEQUENCE {
radioResourceConfigDedicatedSCG-r12 SEQUENCE {
drb-ToAddModListSCG-r12 SEQUENCE (SIZE (1..maxDRB)) OF SEQUENCE {	1 entry
DRB-ToAddModSCG-r12[1] SEQUENCE {
drb-Identity-r12	Same as the DRB ID configured for split DRB in preamble
logicalChannelIdentitySCG-r12	Not present
logicalChannelConfigSCG-r12	Not present
}
}
}
pSCellToAddMod-r12	Not present
mobilityControlInfoSCG-r12 SEQUENCE {
t307-r12	ms2000
ue-IdentitySCG-r12	Not present
rach-ConfigDedicated-r12	Not present
cipheringAlgorithmSCG-r12	Not present
}
}
}
}

7.3.7.3 PDCP Data Recovery / Reconfiguration of Split DRB to MCG/SCG DRBs

7.3.7.3.1 Test Purpose (TP)

(1)

with { UE in connected mode with SCG activated with a Split DRB established using RLC-AM }

ensure that {

when { network requests reconfiguration the Split DRB of the PSCell to a MCG DRB (without handover)}

then { UE establishes the MCG DRB and the SCG DRB and performs retransmission of all the PDCP PDUs previously submitted to re-established AM RLC entity in ascending order of the associated COUNT values from the first PDCP PDU for which the successful delivery has not been confirmed by lower layers on the MCG DRB }

}

7.3.7.3.2 Conformance requirements

References: The conformance requirements covered in the present TC are specified in: 3GPP TS 36.323 clause 5.9 and TS 36.331, clause 5.3.10.10.

[TS 36.323, clause 5.9]

When upper layers request a PDCP Data Recovery for a radio bearer, the UE shall:

After performing the above procedures, the UE shall follow the procedures in subclause 5.1.1.

[TS 36.331, clause 5.3.10.10]

The UE shall:

1> if the received scg-Configuration is set to release or includes the mobilityControlInfoSCG (i.e. SCG release/ change):

2> if mobilityControlInfo is not received (i.e. SCG release/ change without HO):

3> reset SCG MAC, if configured;

3> for each drb-Identity value that is part of the current UE configuration:

4> if the DRB indicated by drb-Identity is an SCG DRB:

5> re-establish the PDCP entity and the SCG RLC entity or entities;

4> if the DRB indicated by drb-Identity is a split DRB:

5> perform PDCP data recovery and re-establish the SCG RLC entity;

…

7.3.7.3.3 Test description

7.3.7.3.3.1 Pre-test conditions

System Simulator:

– Cell 1 is the PCell, and Cell 10 is the PSCell.

– System information combination 3 as defined in TS 36.508 [18] clause 4.4.3.1 is used in E-UTRA Cell 1 and Cell 10.

UE:

None.

Preamble

– The UE is in state DC Split DRB Loopback Activated (state 6B) on Cell 1 and Cell 10 according to [18].

7.3.7.3.3.2 Test procedure sequence

Table 7.3.7.3.3.2-1: Main behaviour

St	Procedure	Message Sequence		TP	Verdict
		U – S	Message
1	The SS is configured on Cell 10 (PSCell) not to send RLC acknowledgements (RLC ACKs) to the UE.
2	The SS creates 3 PDCP Data PDUs and the Next_PDCP_TX_SN is set to "0".	–	–	–	–
–	EXCEPTION: Step 3 and 4 shall be repeated for k=0 to 2 (increment=1).	–	–	–	–
3	The SS sends the PDCP Data PDU #k on the split DRB on Cell 1 (PCell): D/C field = 1 (PDCP Data PDU) and PDCP SN = k. After having sent a PDU, the SS sets Next_PDCP_TX_SN= k+1.	<–	PDCP PDU DATA #k	–	–
4	The UE sends the PDCP Data PDU #k on the AM RLC entity configured for SCG on Cell 10 (PSCell): D/C field = 1 (PDCP Data PDU) and PDCP SN = k. Data is previously received data from PDU #k.	–>	PDCP PDU DATA #k	–	–
5	The SS sends a RRCConnectionReconfiguration message containing ACTIVATE DEDICATED EPS BEARER CONTEXT REQUEST on Cell 1 (PCell) to modify the split DRB to MCG DRB, and add a SCG DRB.	<–	RRCConnectionReconfiguration	–	–
6	The UE transmits a RRCConnectionReconfigurationComplete message on Cell 1 (PCell).	–>	RRCConnectionReconfigurationComplete	–	–
6A	The UE transmits an ULInformationTransfer containing ACTIVATE DEDICATED EPS BEARER CONTEXT ACCEPT message.	–>	ULInformationTransfer
7	The UE sends a PDCP Control PDU on the AM RLC entity configured for MCG on Cell 1 (PCell), with the following content to the SS: D/C field = 0 (PDCP control PDU) and PDU Type =000, FMS field = 3.	–>	PDCP STATUS REPORT	–	–
–	EXCEPTION: Step 8 shall be repeated for k=0 to 2(increment=1).
8	Check: Does the UE sends the PDCP Data PDU #k via on the AM RLC entity configured for MCG on Cell 1 (PCell): D/C field = 1 (PDCP Data PDU) and PDCP SN = k. Data is previously received data from PDU #k ?	–>	PDCP DATA PDU #k	1	P

7.3.7.3.3.3 Specific message contents

Table 7.3.7.3.3.3-1: RRCConnectionReconfiguration (Step 5, Table 7.3.7.3.3.2-1)

Derivation Path: 36.508, Table 4.6.1-8, condition PSCell_Add_SCG_DRB
Information Element	Value/remark	Comment	Condition
RRCConnectionReconfiguration ::= SEQUENCE {}
criticalExtensions CHOICE {
c1 CHOICE{
rrcConnectionReconfiguration-r8 SEQUENCE {
radioResourceConfigDedicated	RadioResourceConfigDedicated-DRBRECONFIG
nonCriticalExtension SEQUENCE {		v890
nonCriticalExtension SEQUENCE {		v920
nonCriticalExtension SEQUENCE {		v1020
nonCriticalExtension SEQUENCE {		v1130
nonCriticalExtension SEQUENCE {		v1250
scg-Configuration-r12 CHOICE {	SCG-Configuration-r12-SCG_DRB
}
}
}
}
}
}
}
}
}

Table 7.3.7.3.3.3-2: SCG-Configuration-r12-SCG_DRB (Table 7.3.7.3.3.3-1)

Derivation Path: 36.508 Table 4.6.3-19F with condition PSCell_Add_SCG_DRB
Information Element	Value/remark	Comment	Condition
scg-Configuration-r12 CHOICE {
setup SEQUENCE {
scg-ConfigPartMCG-r12	Not present
scg-ConfigPartSCG-r12 SEQUENCE {
radioResourceConfigDedicatedSCG-r12 SEQUENCE {
drb-ToAddModListSCG-r12 SEQUENCE (SIZE (1..maxDRB)) OF SEQUENCE {	1 entry
DRB-ToAddModSCG-r12[1] SEQUENCE {
drb-Identity-r12	BID+1	BID is the total number of established DRBs in the UE, before applying the contents of this IE
}
}
}
pSCellToAddMod-r12	Not present
}
}
}

Table 7.3.7.3.3.3-3: RadioResourceConfigDedicated-DRBRECONFIG (Table 7.3.7.3.3.3-1)

Derivation Path: 36.508 Table 4.6.3-27
Information Element	Value/remark	Comment	Condition
RadioResourceConfigDedicated ::= SEQUENCE {
drb-ToAddModList	DRB-ToAddModList-RECONFIG-toMCG
}

Table 7.3.7.3.3.3-4: DRB-ToAddModList-RECONFIG-toMCG (Table 7.3.7.3.3.3-3)

Derivation Path: 36.508 Table 4.6.3-2A
Information Element	Value/remark	Comment	Condition
DRB-ToAddModList ::= SEQUENCE (SIZE (1..maxDRB)) OF SEQUENCE {	1 Entry
eps-BearerIdentity	Not present
drb-Identity	Same as the DRB ID configured for split DRB in preamble
pdcp-Config	Not present
rlc-Config	Not present
logicalChannelIdentity	Not present
logicalChannelConfig	Not present
drb-TypeChange-r12	toMCG
}

7.3.7.4 PDCP re-establishment at handover / Split DRB

7.3.7.4.1 Test Purpose (TP)

(1)

with { UE in connected mode with SCG activated with a Split DRB established }

ensure that {

when { the UE receives a RRCConnectionReconfiguration message including mobilityControlInfo }

then { the UE re-establish PDCP for all established radio bearers and process the PDCP PDUs stored by the reordering function }

}

7.3.7.4.2 Conformance requirements

References: The conformance requirements covered in the present TC are specified in: 3GPP TS 36.323 clause 5.2.2.1a, 3GPP TS 36.331 clause 5.3.5.4.

[TS 36.323, clause 5.2.2.1a]

When upper layers request a PDCP re-establishment while the reordering function is used, the UE shall:

– process the PDCP Data PDU(s) that are received from lower layers due to the re-establishment of the lower layers, as specified in the subclause 5.1.2.1.4;

– if the PDCP entity is to be associated with one AM RLC entity after PDCP re-establishment:

– stop and reset t-Reordering;

– apply the ciphering algorithm and key provided by upper layers during the re-establishment procedure.

[TS 36.331, clause 5.3.5.4]

If the RRCConnectionReconfiguration message includes the mobilityControlInfo and the UE is able to comply with the configuration included in this message, the UE shall:

1> stop timer T310, if running;

1> stop timer T312, if running;

1> start timer T304 with the timer value set to t304, as included in the mobilityControlInfo;

1> if the carrierFreq is included:

2> consider the target PCell to be one on the frequency indicated by the carrierFreq with a physical cell identity indicated by the targetPhysCellId;

1> else:

2> consider the target PCell to be one on the frequency of the source PCell with a physical cell identity indicated by the targetPhysCellId;

1> start synchronising to the DL of the target PCell;

NOTE 1: The UE should perform the handover as soon as possible following the reception of the RRC message triggering the handover, which could be before confirming successful reception (HARQ and ARQ) of this message.

1> reset MCG MAC and SCG MAC, if configured;

1> re-establish PDCP for all RBs that are established;

NOTE 2: The handling of the radio bearers after the successful completion of the PDCP re-establishment, e.g. the re-transmission of unacknowledged PDCP SDUs (as well as the associated status reporting), the handling of the SN and the HFN, is specified in TS 36.323 [8].

1> re-establish MCG RLC and SCG RLC, if configured, for all RBs that are established;

…

1> if the received RRCConnectionReconfiguration includes the scg-Configuration; or

1> if the current UE configuration includes one or more split DRBs and the received RRCConnectionReconfiguration includes radioResourceConfigDedicated including drb-ToAddModList:

2> perform SCG reconfiguration as specified in 5.3.10.10;

7.3.7.4.3 Test description

7.3.7.4.3.1 Pre-test conditions

System Simulator:

– Cell 1 is the Pcell, Cell 2 is the intrafrequency neighbour cell and Cell 10 is the PSCell.

– System information combination 3 as defined in TS 36.508 [18] clause 4.4.3.1 is used in E-UTRA Cell 1, Cell 2 and Cell 10.

UE:

None.

Preamble

– The UE is in state DC Split DRB Loopback Activated (state 6B) on Cell 1 and Cell 10 according to [18].

7.3.7.4.3.2 Test procedure sequence

Table 7.3.7.4.3.2-1 illustrates the downlink power levels and other changing parameters to be applied for the cells at various time instants of the test execution. Row marked "T0" denotes the initial conditions after preamble, while columns marked "T1" is to be applied subsequently. The exact instants on which these values shall be applied are described in the texts in this clause.

Table 7.3.7.4.3.2-1: Time instances of cell power level and parameter changes

	Parameter	Unit	Cell 1	Cell 2	Cell 10	Remark
T0	Cell-specific RS EPRE	dBm/15kHz	-73	-97	-75	The power level values are such that measurement results for Cell 1 (M1) and Cell 3 (M3) satisfy exit condition for event A3 (M3 < M1).
T1	Cell-specific RS EPRE	dBm/15kHz	-85	-80	-75	The power level values are such that measurement results for Cell 1 (M1) and Cell 3 (M3) satisfy entry condition for event A3 (M3 > M1).

Table 7.3.7.4.3.2-2: Main behaviour

St	Procedure	Message Sequence		TP	Verdict
		U – S	Message
1	The SS sends a PDCP Data PDU on the split DRB on Cell 1 (PCell) the PDCP Sequence number is 0.	<–	PDCP DATA PDU	–	–
2	The UE transmit a PDCP Data PDU on the AM RLC entity of the split DRB configured for SCG on Cell 10 (PSCell)	–>	PDCP DATA PDU	–	–
3	The SS sends a PDCP Data PDU on the MCG DRB on Cell 1 (PCell) the PDCP Sequence number is 0.	<–	PDCP DATA PDU	–	–
4	The UE transmit a PDCP Data PDU on the AM RLC entity configured for MCG on Cell 1 (PCell) , the PDCP Sequence number is 0.	–>	PDCP DATA PDU	–	–
5	The SS sends 3 PDCP Data PDU’s on the split DRB on Cell 1 (PCell), PDCP Sequence numbers are 10 , 500 (Within Reordering_Window) and 2600 (outside Reordering_Window).	<–	PDCP DATA PDU’s	–	–
6	The SS sends 3 PDCP Data PDU’s on the MCG DRB on Cell 1 (PCell), the PDCP Sequence number is 10 , 500 (Within Reordering_Window) and 2600 (outside Reordering_Window).	<–	PDCP DATA PDU’s	–	–
7	The SS changes Cell 1 and Cell 2 parameters according to the row "T1" in table 7.3.7.4.3.2-1.	–	–	–	–
8	The SS transmits an RRCConnectionReconfiguration message on Cell 1 to order the UE to perform intra frequency handover to Cell 2.	<–	RRCConnectionReconfiguration	–	–
–	EXCEPTION: the behaviour in table 7.3.7.4.3.2-3 runs in parallel with steps 9, 10 and 11 below.	–	–	–	–
–	EXCEPTION: Steps 9, 10 and 11 can occur in any order	–	–	–	–
9	Check: Does the UE transmit an RRCConnectionReconfigurationComplete message on Cell 2 to confirm the successful completion of the intra frequency handover?	–>	RRCConnectionReconfigurationComplete	1	P
10	Check: Does the UE transmit 2 loop back PDCP Data PDU on the AM RLC entity of the split DRB configured for SCG on Cell 10 (PSCell) corresponding to PDCP PDU with Sequence number 10 and 500 in step 5?	–>	PDCP DATA PDU’s	1	P
11	Check: Does the UE transmit 2 loop back PDCP Data PDU on the AM RLC entity configured for MCG on Cell 2 (PCell) corresponding to PDCP PDU with Sequence number 10 and 500 in step 6 ?	–>	PDCP DATA PDU’s	1	P

Table 7.3.7.4.3.2-3: Parallel behaviour

St	Procedure	Message Sequence		TP	Verdict
		U – S	Message
–	EXCEPTION: Steps 1 and 2 can occur in any order	–	–	–	–
1	Check: Does the UE transmit loop back PDCP Data PDU on the AM RLC entity of the split DRB configured for SCG on Cell 10 (PSCell) corresponding to PDCP PDU with Sequence number 2600 in step 5 ?	–>	PDCP DATA PDU	1	F
2	Check: Does the UE transmit loop back PDCP Data PDU on the AM RLC entity configured for MCG on Cell 2 (PCell) corresponding to PDCP PDU with Sequence number 2600 in step 6 ?	–>	PDCP DATA PDU	1	F

7.3.7.4.3.3 Specific message contents

Table 7.3.7.4.3.3-1: RRCConnectionReconfiguration (Step 8, Table 7.3.7.4.3.2-1)

Derivation Path: 36.508, Table 4.6.1-8, condition HO
Information Element	Value/remark	Comment	Condition
RRCConnectionReconfiguration ::= SEQUENCE {
criticalExtensions CHOICE {
c1 CHOICE{
rrcConnectionReconfiguration-r8 SEQUENCE {
mobilityControlInfo SEQUENCE {		MobilityControlInfo-HO
targetPhysCellId	PhysicalCellIdentity of Cell 2
carrierFreq	Not present
}
}
}
}
}

7.3.7.5 PDCP re-establishment at handover of MCG/SCG DRBs and at SCG change without handover with SCG DRB change

7.3.7.5.1 Test Purpose (TP)

(1)

with { UE in connected mode with SCG activated with a MCG/SCG DRBs established }

ensure that {

when { the UE receives a RRCConnectionReconfiguration message including mobilityControlInfo }

then { the UE re-establish PDCP for all established MCG/ SCG DRBs }

}

(2)

with { UE in connected mode with SCG activated with a MCG/SCG DRB established }

ensure that {

when { the UE receives a RRCConnectionReconfiguration message without mobilityControlInfo IE and with a scg-Configuration IE to modify the SCG DRB }

then { the UE performs PDCP re-establishment on all established MCG/SCG DRBs }

}

7.3.7.5.2 Conformance requirements

References: The conformance requirements covered in the present TC are specified in: 3GPP TS 36.323 clause 5.2.2.1a, 3GPP TS 36.331 clauses 5.3.5.4, 5.3.10.10.

[TS 36.323, clause 5.2.2.1a]

When upper layers request a PDCP re-establishment while the reordering function is used, the UE shall:

– process the PDCP Data PDU(s) that are received from lower layers due to the re-establishment of the lower layers, as specified in the subclause 5.1.2.1.4;

– if the PDCP entity is to be associated with one AM RLC entity after PDCP re-establishment:

– stop and reset t-Reordering;

– apply the ciphering algorithm and key provided by upper layers during the re-establishment procedure.

[TS 36.331, clause 5.3.5.4]

If the RRCConnectionReconfiguration message includes the mobilityControlInfo and the UE is able to comply with the configuration included in this message, the UE shall:

1> stop timer T310, if running;

1> stop timer T312, if running;

1> start timer T304 with the timer value set to t304, as included in the mobilityControlInfo;

1> if the carrierFreq is included:

2> consider the target PCell to be one on the frequency indicated by the carrierFreq with a physical cell identity indicated by the targetPhysCellId;

1> else:

2> consider the target PCell to be one on the frequency of the source PCell with a physical cell identity indicated by the targetPhysCellId;

1> start synchronising to the DL of the target PCell;

1> reset MCG MAC and SCG MAC, if configured;

1> re-establish PDCP for all RBs that are established;

1> re-establish MCG RLC and SCG RLC, if configured, for all RBs that are established;

[TS 36.331, clause 5.3.10.10]

The UE shall:

1> if the received scg-Configuration is set to release or includes the mobilityControlInfoSCG (i.e. SCG release/ change):

2> if mobilityControlInfo is not received (i.e. SCG release/ change without HO):

3> reset SCG MAC, if configured;

3> for each drb-Identity value that is part of the current UE configuration:

4> if the DRB indicated by drb-Identity is an SCG DRB:

5> re-establish PDCP and the SCG RLC entity;

4> if the DRB indicated by drb-Identity is a split DRB:

5> perform PDCP data recovery and re-establish the SCG RLC entity;

4> if the DRB indicated by drb-Identity is an MCG DRB; and

4> drb-ToAddModListSCG is received and includes the drb-Identity value, while for this entry drb-Type is included and set to scg (i.e. MCG to SCG):

5> re-establish PDCP and the MCG RLC entity;

3> configure lower layers to consider the SCell(s), except for the PSCell, to be in deactivated state;

7.3.7.5.3 Test description

7.3.7.5.3.1 Pre-test conditions

System Simulator:

– Cell 1 is the Pcell, Cell 2 is the intrafrequency neighbour cell , Cell 10 is the PSCell and Cell 30 is the intrafrequency neighbour cell of cell 10.

– System information combination 3 as defined in TS 36.508 [18] clause 4.4.3.1 is used in E-UTRA Cell 1, Cell 2 cell 10and Cell 30.

UE:

None.

Preamble

– The UE is in state DC MCG/SCG DRB Loopback Activated (state 6A) on Cell 1 and Cell 10 according to [18].

7.3.7.5.3.2 Test procedure sequence

Table 7.3.7.5.3.2-1 illustrates the downlink power levels and other changing parameters to be applied for the cells at various time instants of the test execution. Row marked "T0" denotes the initial conditions after preamble, while columns marked "T1, T2" are to be applied subsequently. The exact instants on which these values shall be applied are described in the texts in this clause.

Table 7.3.7.5.3.2-1: Time instances of cell power level and parameter changes

	Parameter	Unit	Cell 1	Cell 2	Cell 10	Cell 30	Remark
T0	Cell-specific RS EPRE	dBm/15kHz	-73	-97	-75	-97	The power level values are such that measurement results for Cell 1 (M1) and Cell 3 (M3) satisfy exit condition for event A3 (M3 < M1).
T1	Cell-specific RS EPRE	dBm/15kHz	-85	-80	-75	-97	The power level values are such that measurement results for Cell 1 (M1) and Cell 3 (M3) satisfy entry condition for event A3 (M3 > M1).
T2	Cell-specific RS EPRE	dBm/15kHz	-85	-80	-85	-80	The power level values are such that measurement results for Cell 1 (M1) and Cell 3 (M3) satisfy entry condition for event A3 (M3 > M1).

Table 7.3.7.5.3.2-2: Main behaviour

St	Procedure	Message Sequence		TP	Verdict
		U – S	Message
1	The SS sends a PDCP Data PDU on the SCG DRB on Cell 10 (PSCell) the PDCP Sequence number is 0.	<–	PDCP DATA PDU	–	–
2	The UE transmit a PDCP Data PDU on the AM RLC entity of the SCG DRB on Cell 10 (PSCell) the PDCP Sequence number is 0.	–>	PDCP DATA PDU	–	–
3	The SS sends a PDCP Data PDU on the MCG DRB on Cell 1 (PCell) the PDCP Sequence number is 0.	<–	PDCP DATA PDU	–	–
4	The UE transmit a PDCP Data PDU on the AM RLC entity configured for MCG on Cell 1 (PCell) the PDCP Sequence number is 0.	–>	PDCP DATA PDU	–	–
5	The SS sends 3 PDCP Data PDU’s on the SCG DRB on Cell 10 (PSCell), the PDCP Sequence numbers are 10 , 500 (Within Reordering_Window) and 2600 (outside Reordering_Window).	<–	PDCP DATA PDU’s	–	–
6	The SS sends 3 PDCP Data PDU’s on the MCG DRB on Cell 1 (PCell), PDCP Sequence number is 10 , 500 (Within Reordering_Window) and 2600 (outside Reordering_Window).	<–	PDCP DATA PDU’s	–	–
7	The SS changes Cell 1 and Cell 2 parameters according to the row "T1" in table 7.3.7.5.3.2-1.	–	–	–	–
8	The SS transmits an RRCConnectionReconfiguration message on Cell 1 to order the UE to perform intra frequency handover to Cell 2.	<–	RRCConnectionReconfiguration	–	–
–	EXCEPTION: the behaviour in table 7.3.7.5.3.2-3 runs in parallel with steps 9, 10 and 11 below.	–	–	–	–
–	EXCEPTION: Steps 9, 10 and 11 can occur in any order	–	–	–	–
9	Check: Does the UE transmit an RRCConnectionReconfigurationComplete message on Cell 2 to confirm the successful completion of the intra frequency handover?	–>	RRCConnectionReconfigurationComplete	1	P
10	Check: Does the UE transmit 2 loop back PDCP Data PDU on the AM RLC entity of the SCG DRB on Cell 10 (PSCell) corresponding to PDCP PDU with Sequence number 10 and 500 in step 5?	–>	PDCP DATA PDU’s	1	P
11	Check: Does the UE transmit 2 loop back PDCP Data PDU on the AM RLC entity configured for MCG on Cell 2 (PCell) corresponding to PDCP PDU with Sequence number 10 and 500 in step 6 ?	–>	PDCP DATA PDU’s	1	P
12	The SS sends a PDCP Data PDU on the SCG DRB on Cell 10 (PSCell) the PDCP Sequence number is 0.	<–	PDCP DATA PDU	–	–
13	UE transmit a PDCP Data PDU on the AM RLC entity of the SCG DRB on Cell 10 (PSCell) the PDCP Sequence number is 0.	–>	PDCP DATA PDU	–	–
14	The SS sends a PDCP Data PDU on the MCG DRB on Cell 2 (PCell) the PDCP Sequence number is 0.	<–	PDCP DATA PDU	–	–
15	UE transmit a PDCP Data PDU on the AM RLC entity configured for MCG on Cell 2 (PSCell) the PDCP Sequence number is 0.	–>	PDCP DATA PDU	–	–
16	The SS sends 3 PDCP Data PDU’s on the SCG DRB on Cell 10 (PSCell), the PDCP Sequence numbers are 10, 500 (Within Reordering_Window) and 2600 (outside Reordering_Window).	<–	PDCP DATA PDU’s	–	–
17	The SS sends 3 PDCP Data PDU’s on the MCG DRB on Cell 2 (PCell), the PDCP Sequence numbers are 10 , 500 (Within Reordering_Window) and 2600 (outside Reordering_Window).	<–	PDCP DATA PDU’s	–	–
18	The SS changes Cell 10 and Cell 30 parameters according to the row "T2" in table 7.3.7.5.3.2-1.	–	–	–	–
19	The SS transmits an RRCConnectionReconfiguration message on Cell 2 to order the UE to perform SCG change to Cell 30.	<–	RRCConnectionReconfiguration	–	–
–	EXCEPTION: the behaviour in table 7.3.7.5.3.2-4 runs in parallel with steps 20, 21 and 22 below.	–	–	–	–
–	EXCEPTION: Step 20, 21 and 22 can occur in any order	–	–	–	–
20	Check: Does the UE transmit an RRCConnectionReconfigurationComplete message on Cell 2 to confirm the successful completion of the SCG change to Cell 30?	–>	RRCConnectionReconfigurationComplete	2	P
21	Check: Does the UE transmit 2 loop back PDCP Data PDU on the AM RLC entity of the SCG DRB on Cell 30 (PSCell) corresponding to PDCP PDU with Sequence number 10 and 500 in step 16?	–>	PDCP DATA PDU’s	2	P
22	Check: Does the UE transmit 2 loop back PDCP Data PDU on the AM RLC entity configured for MCG on Cell 2 (PCell) corresponding to PDCP PDU with Sequence number 10 and 500 in step17 ?	–>	PDCP DATA PDU’s	2	P

Table 7.3.7.5.3.2-3: Parallel behaviour

St	Procedure	Message Sequence		TP	Verdict
		U – S	Message
–	EXCEPTION: Steps 1 and 2 can occur in any order	–	–	–	–
1	Check: Does the UE transmit loop back PDCP Data PDU on the AM RLC entity of the SCG DRB on Cell 10 (PSCell) corresponding to PDCP PDU with Sequence number 2600 in step 5 ?	–>	PDCP DATA PDU	1	F
2	Check: Does the UE transmit loop back PDCP Data PDU on the AM RLC entity configured for MCG on Cell 2 (PCell) corresponding to PDCP PDU with Sequence number 2600 in step 6 ?	–>	PDCP DATA PDU	1	F

Table 7.3.7.5.3.2-4: Parallel behaviour

St	Procedure	Message Sequence		TP	Verdict
		U – S	Message
–	EXCEPTION: Steps 1 and 2 can occur in any order	–	–	–	–
1	Check: Does the UE transmit loop back PDCP Data PDU on the AM RLC entity of the SCG DRB on Cell 30 (PSCell) corresponding to PDCP PDU with Sequence number 2600 in step 16 ?	–>	PDCP DATA PDU	2	F
2	Check: Does the UE transmit loop back PDCP Data PDU on the AM RLC entity configured for MCG on Cell 2 (PCell) corresponding to PDCP PDU with Sequence number 2600 in step 17 ?	–>	PDCP DATA PDU	2	F

7.3.7.5.3.3 Specific message contents

Table 7.3.7.5.3.3-1: RRCConnectionReconfiguration (Step 8, Table 7.3.7.5.3.2-1)

Derivation Path: 36.508, Table 4.6.1-8, condition HO
Information Element	Value/remark	Comment	Condition
RRCConnectionReconfiguration ::= SEQUENCE {
criticalExtensions CHOICE {
c1 CHOICE{
rrcConnectionReconfiguration-r8 SEQUENCE {
mobilityControlInfo SEQUENCE {		MobilityControlInfo-HO
targetPhysCellId	PhysicalCellIdentity of Cell 2
carrierFreq	Not present
}
}
}
}
}

Table 7.3.7.5.3.3-2: RRCConnectionReconfiguration (Step 19, Table 7.3.7.5.3.2-1)

Derivation Path: 36.508, Table 4.6.1-8, condition PSCell_Mod
Information Element	Value/remark	Comment	Condition
RRCConnectionReconfiguration ::= SEQUENCE {
criticalExtensions CHOICE {
c1 CHOICE{
nonCriticalExtension SEQUENCE {
nonCriticalExtension SEQUENCE {
nonCriticalExtension SEQUENCE {
nonCriticalExtension SEQUENCE {
nonCriticalExtension SEQUENCE {
scg-Configuration-r12	SCG-Configuration-r12-DEFAULT
}
}
}
}
}
}
}

Table 7.3.7.5.3.3-3: SCG-Configuration-r12-DEFAULT(Step 19, Table 7.3.7.5.3.3-2)

Derivation Path: 36.508, Table 4.6.3-19F cond ition PSCell_AddMod
Information Element	Value/remark		Comment	Condition
scg-Configuration-r12 CHOICE {
setup SEQUENCE {
scg-ConfigPartMCG-r12	Not Present
scg-ConfigPartSCG-r12 SEQUENCE {
radioResourceConfigDedicatedSCG-r12 SEQUENCE	Not Present
sCellToReleaseListSCG-r12	Not Present
pSCellToAddMod-r12	NotPresent
sCellToAddModListSCG-r12	Not Present
mobilityControlInfoSCG-r12{
t307-r12	ms1000	ENUMERATED {ms50, ms100, ms150, ms200, ms500,ms1000, ms2000}
ue-IdentitySCG-r12	Not Present
rach-ConfigDedicated-r12	Not Present
cipheringAlgorithmSCG-r12	Not Present
}
}

7.3.7.6 PDCP reordering of Split DRB / Maximum re-ordering delay below t-Reordering

7.3.7.6.1 Test Purpose (TP)

(1)

with { UE in connected mode with DC operation active on a MCG Pcell and a SCG PSCell with a Split DRB established using RLC-AM }

ensure that {

when { a PDCP PDU is received from the lower layers and the SN = Next_PDCP_RX_SN }

then { UE delivers the resulting PDCP SDU directly to upper layer }

}

(2)

with { UE in connected mode with DC operation active on a MCG Pcell and a SCG PSCell with a Split DRB established using RLC-AM }

ensure that {

when { a PDCP PDU is received from the lower layers and the SN is out of the re-ordering window }

then { UE discards the PDCP PDU }

}

(3)

with { UE in connected mode with DC operation active on a MCG Pcell and a SCG PSCell with a Split DRB established using RLC-AM }

ensure that {

when { a PDCP PDU is received from the lower layers and the SN is within the re-ordering window }

then { UE stores the resulting PDCP SDU }

}

(4)

with { UE in connected mode with DC operation active on a MCG Pcell and a SCG PSCell with a Split DRB established using RLC-AM, and the Reordering_PDCP_RX_COUNT is not equal to the COUNT value associated to RX_HFN and Next_PDCP_RX_SN (there is missing PDCP PDUs) }

ensure that {

when { a PDCP PDU is received from the lower layers and the SN = Last_Submitted_PDCP_RX_SN + 1 or the SN = Last_Submitted_PDCP_RX_SN – Maximum_PDCP_SN }

then { UE delivers the resulting PDCP SDU and all stored PDCP SDUs with consecutive COUNT value to upper layer, in ascending order }

}

7.3.7.6.2 Conformance requirements

References: The conformance requirements covered in the present TC are specified in: 3GPP TS 36.323 clause 5.1.2.1.4.

[TS 36.323, clause 5.1.2.1.4]

For DRBs mapped on RLC AM, the PDCP entity shall use the reordering function as specified in this section when:

– the PDCP entity is associated with two AM RLC entities; or

– the PDCP entity is associated with one AM RLC entity after it was, according to the most recent reconfiguration, associated with two AM RLC entities without performing PDCP re-establishment.

The PDCP entity shall not use the reordering function in other cases.

[TS 36.323, clause 5.1.2.1.4.1]

For DRBs mapped on RLC AM, when there ordering function is used, at reception of a PDCP Data PDU from lower layers, the UE shall:

– if received PDCP SN – Last_Submitted_PDCP_RX_SN > Reordering_Window or 0 <= Last_Submitted_PDCP_RX_SN – received PDCP SN < Reordering_Window:

– discard the PDCP PDU;

– else if Next_PDCP_RX_SN – received PDCP SN > Reordering_Window:

– increment RX_HFN by one;

– use COUNT based on RX_HFN and the received PDCP SN for deciphering the PDCP PDU;

– set Next_PDCP_RX_SN to the received PDCP SN + 1;

– else if received PDCP SN – Next_PDCP_RX_SN >= Reordering_Window:

– use COUNT based on RX_HFN – 1 and the received PDCP SN for deciphering the PDCP PDU;

– else if received PDCP SN >= Next_PDCP_RX_SN:

– use COUNT based on RX_HFN and the received PDCP SN for deciphering the PDCP PDU;

– set Next_PDCP_RX_SN to the received PDCP SN + 1;

– if Next_PDCP_RX_SN is larger than Maximum_PDCP_SN:

– set Next_PDCP_RX_SN to 0;

– increment RX_HFN by one;

– else if received PDCP SN < Next_PDCP_RX_SN:

– use COUNT based on RX_HFN and the received PDCP SN for deciphering the PDCP PDU;

– if the PDCP PDU has not been discarded in the above:

– if a PDCP SDU with the same PDCP SN is stored:

– discard the PDCP PDU;

– else:

– perform deciphering of the PDCP PDU and store the resulting PDCP SDU;

– if received PDCP SN = Last_Submitted_PDCP_RX_SN + 1 or received PDCP SN = Last_Submitted_PDCP_RX_SN – Maximum_PDCP_SN:

– deliver to upper layers in ascending order of the associated COUNT value:

– all stored PDCP SDU(s) with consecutively associated COUNT value(s) starting from the COUNT value associated with the received PDCP PDU;

– set Last_Submitted_PDCP_RX_SN to the PDCP SN of the last PDCP SDU delivered to upper layers;

– if t-Reordering is running:

– if the PDCP SDU with Reordering_PDCP_RX_COUNT – 1 has been delivered to upper layers:

– stop and reset t-Reordering;

– if t-Reordering is not running (includes the case when t-Reordering is stopped due to actions above):

– if there is at least one stored PDCP SDU:

– start t-Reordering;

– set Reordering_PDCP_RX_COUNT to the COUNT value associated to RX_HFN and Next_PDCP_RX_SN.

7.3.7.6.3 Test description

7.3.7.6.3.1 Pre-test conditions

System Simulator:

– Cell 1 is the PCell, and Cell 10 is the PSCell.

– System information combination 3 as defined in TS 36.508 [18] clause 4.4.3.1 is used in E-UTRA Cell 1 and Cell 10.

UE:

None.

Preamble

– The UE is in state DC Split DRB Loopback Activated (state 6B) on Cell 1 and Cell 10 according to [18].

7.3.7.6.3.2 Test procedure sequence

Table 7.3.7.6.3.2-1: Main behaviour

St	Procedure	Message Sequence		TP	Verdict
		U – S	Message
1	The SS sends the PDCP SDU #0 on the split DRB on Cell 1 (PCell): D/C field = 1 (PDCP Data PDU) and PDCP SN = 0.	<–	(PDCP SDU #0)	–	–
2	Check: Does the UE transmit the PDCP SDU #0 via the AM RLC entity configured for SCG on Cell 10 (PSCell): D/C field = 1 (PDCP Data PDU) and PDCP SN = 0	–>	(PDCP SDU #0)	1	P
3	The SS sends the PDCP SDU #0 on the split DRB on Cell 10 (PSCell): D/C field = 1 (PDCP Data PDU) and PDCP SN = 0. (Note 1)	<–	(PDCP SDU #0)	–	–
4	Check: Does the UE transmit a PDCP SDU via the AM RLC entity configured for SCG on Cell 10 (PSCell) in the next 1s.	–>	(PDCP SDU)	2	F
5	The SS sends the PDCP SDU #2049 on the split DRB on Cell 1 (PCell): D/C field = 1 (PDCP Data PDU) and PDCP SN = 2049. (Note 1)	<–	(PDCP SDU #2049)	–	–
6	Check: Does the UE transmit a PDCP SDU via the AM RLC entity configured for SCG on Cell 10 (PSCell) in the next 1s.	–>	(PDCP SDU)	2	F
7	The SS sends the PDCP SDU #2 on the split DRB on Cell 1 (PCell): D/C field = 1 (PDCP Data PDU) and PDCP SN = 2. The UE starts t-Reordering.	<–	(PDCP SDU #2)	–	–
8	The SS sends the PDCP SDU #3 on the split DRB on Cell 10 (PSCell): D/C field = 1 (PDCP Data PDU) and PDCP SN =3.	<–	(PDCP SDU #3)	–	–
9	The SS sends the PDCP SDU #1 on the split DRB on Cell 10 (PSCell): D/C field = 1 (PDCP Data PDU) and PDCP SN = 1.	<–	(PDCP SDU #1)	–	–
10	Check: Does the UE transmit the PDCP SDU #1 via the AM RLC entity configured for SCG on Cell 10 (PSCell): D/C field = 1 (PDCP Data PDU) and PDCP SN = 1	–>	(PDCP SDU #1)	3, 4	P
11	Check: Does the UE transmit the PDCP SDU #2 via the AM RLC entity configured for SCG on Cell 10 (PSCell) D/C field = 1 (PDCP Data PDU) and PDCP SN = 2	–>	(PDCP SDU #2)	3, 4	P
12	Check: Does the UE transmit the PDCP SDU #3 via the AM RLC entity configured for SCG on Cell 10 (PSCell) D/C field = 1 (PDCP Data PDU) and PDCP SN = 3	–>	(PDCP SDU #3)	3, 4	P
Note 1: The Reordering_Window size is 2048 when 12 bit SN length is used.

7.3.7.6.3.3 Specific message contents

None.

7.3.7.7 PDCP reordering of Split DRB / t-Reordering timer operations

7.3.7.7.1 Test Purpose (TP)

(1)

with { UE in connected mode with DC operation active on a MCG Pcell and a SCG PSCell with a Split DRB established using RLC-AM and the associated PDCP t-Reordering timer is running }

ensure that {

when { a PDCP SDU with Reordering_PDCP_RX_COUNT – 1 has been delivered to upper layers }

then { UE stops and resets t-Reordering timer }

}

(2)

with { UE in connected mode with DC operation active on a MCG Pcell and a SCG PSCell with a Split DRB established using RLC-AM and the associated PDCP t-Reordering timer is running }

ensure that {

when { the t-Reordering timer expires }

then { UE delivers all stored PDCP SDUs to upper layer }

}

(3)

with { UE in connected mode with DC operation active on a MCG Pcell and a SCG PSCell with a Split DRB established using RLC-AM and the associated PDCP t-Reordering timer is running }

ensure that {

when { the t-Reordering is reconfigured by upper layers }

then { UE stops and resets t-Reordering timer }

}

7.3.7.7.2 Conformance requirements

References: The conformance requirements covered in the present TC are specified in: 3GPP TS 36.323 clause 5.1.2.1.4.

[TS 36.323, clause 5.1.2.1.4]

For DRBs mapped on RLC AM, the PDCP entity shall use the reordering function as specified in this section when:

– the PDCP entity is associated with two AM RLC entities; or

– the PDCP entity is associated with one AM RLC entity after it was, according to the most recent reconfiguration, associated with two AM RLC entities without performing PDCP re-establishment.

The PDCP entity shall not use the reordering function in other cases.

[TS 36.323, clause 5.1.2.1.4.1]

For DRBs mapped on RLC AM, when there ordering function is used, at reception of a PDCP Data PDU from lower layers, the UE shall:

– if received PDCP SN – Last_Submitted_PDCP_RX_SN > Reordering_Window or 0 <= Last_Submitted_PDCP_RX_SN – received PDCP SN < Reordering_Window:

– discard the PDCP PDU;

– else if Next_PDCP_RX_SN – received PDCP SN > Reordering_Window:

– increment RX_HFN by one;

– use COUNT based on RX_HFN and the received PDCP SN for deciphering the PDCP PDU;

– set Next_PDCP_RX_SN to the received PDCP SN + 1;

– else if received PDCP SN – Next_PDCP_RX_SN >= Reordering_Window:

– use COUNT based on RX_HFN – 1 and the received PDCP SN for deciphering the PDCP PDU;

– else if received PDCP SN >= Next_PDCP_RX_SN:

– use COUNT based on RX_HFN and the received PDCP SN for deciphering the PDCP PDU;

– set Next_PDCP_RX_SN to the received PDCP SN + 1;

– if Next_PDCP_RX_SN is larger than Maximum_PDCP_SN:

– set Next_PDCP_RX_SN to 0;

– increment RX_HFN by one;

– else if received PDCP SN < Next_PDCP_RX_SN:

– use COUNT based on RX_HFN and the received PDCP SN for deciphering the PDCP PDU;

– if the PDCP PDU has not been discarded in the above:

– if a PDCP SDU with the same PDCP SN is stored:

– discard the PDCP PDU;

– else:

– perform deciphering of the PDCP PDU and store the resulting PDCP SDU;

– if received PDCP SN = Last_Submitted_PDCP_RX_SN + 1 or received PDCP SN = Last_Submitted_PDCP_RX_SN – Maximum_PDCP_SN:

– deliver to upper layers in ascending order of the associated COUNT value:

– all stored PDCP SDU(s) with consecutively associated COUNT value(s) starting from the COUNT value associated with the received PDCP PDU;

– set Last_Submitted_PDCP_RX_SN to the PDCP SN of the last PDCP SDU delivered to upper layers;

– if t-Reordering is running:

– if the PDCP SDU with Reordering_PDCP_RX_COUNT – 1 has been delivered to upper layers:

– stop and reset t-Reordering;

– if t-Reordering is not running (includes the case when t-Reordering is stopped due to actions above):

– if there is at least one stored PDCP SDU:

– start t-Reordering;

– set Reordering_PDCP_RX_COUNT to the COUNT value associated to RX_HFN and Next_PDCP_RX_SN.

[TS 36.323, clause 5.1.2.1.4.2]

When t-Reordering expires, the UE shall:

– deliver to upper layers in ascending order of the associated COUNT value:

– all stored PDCP SDU(s) with associated COUNT value(s) less than Reordering_PDCP_RX_COUNT;

– all stored PDCP SDU(s) with consecutively associated COUNT value(s) starting from Reordering_PDCP_RX_COUNT;

– set Last_Submitted_PDCP_RX_SN to the PDCP SN of the last PDCP SDU delivered to upper layers;

– if there is at least one stored PDCP SDU:

– start t-Reordering;

– set Reordering_PDCP_RX_COUNT to the COUNT value associated to RX_HFN and Next_PDCP_RX_SN.

[TS 36.323, clause 5.1.2.1.4.3]

When the value of the t-Reordering is reconfigured by upper layers while the t-Reordering is running, the UE shall:

– stop and restart t-Reordering;

– set Reordering_PDCP_RX_COUNT to the COUNT value associated to RX_HFN and Next_PDCP_RX_SN.

7.3.7.7.3 Test description

7.3.7.7.3.1 Pre-test conditions

System Simulator:

– Cell 1 is the PCell, and Cell 10 is the PSCell.

– System information combination 3 as defined in TS 36.508 [18] clause 4.4.3.1 is used in E-UTRA Cell 1 and Cell 10.

UE:

None.

Preamble

– The UE is in state DC Split DRB Loopback Activated (state 6B) on Cell 1 and Cell 10 according to [18].

Note: The PDCP t-Reordering is configured with the default value of 200ms.

7.3.7.7.3.2 Test procedure sequence

Table 7.3.7.7.3.2-1: Main behaviour

St	Procedure	Message Sequence		TP	Verdict
		U – S	Message
1	The SS sends the PDCP SDU #1 on the split DRB on Cell 1 (PCell): D/C field = 1 (PDCP Data PDU) and PDCP SN = 1. The UE starts t-Reordering.	<–	(PDCP SDU #1)	–	–
2	Wait for 100ms (< configured t-Reordering)	–	–	–	–
3	The SS sends the PDCP SDU #4 on the split DRB on Cell 10 (PSCell): D/C field = 1 (PDCP Data PDU) and PDCP SN = 4.	<–	(PDCP SDU #4)	–	–
4	The SS sends the PDCP SDU #0 on the split DRB on Cell 10 (PSCell): D/C field = 1 (PDCP Data PDU) and PDCP SN = 0. The UE restarts t-Reordering timer Note T₁	<–	(PDCP SDU #0)	–	–
5	Check: Does the UE transmit the PDCP SDU #0 via the AM RLC entity configured for SCG on Cell 10 (PSCell)?	–>	(PDCP SDU #0)	1	P
6	Check: Does the UE transmit the PDCP SDU #1 via the AM RLC entity configured for SCG on Cell 10 (PSCell)?	–>	(PDCP SDU #1)	1	P
7	Check1: Does the UE transmit the PDCP SDU #4 via the AM RLC entity configured for SCG on Cell 10 (PSCell) after t-Reordering expiry? Note T₂ Check 2: Is (T₂ – T₁) > t-Reordering?	–>	(PDCP SDU #4)	2	P
8	The SS sends the PDCP SDU #6 on the split DRB on Cell 10 (PSCell): D/C field = 1 (PDCP Data PDU) and PDCP SN = 6. The UE starts t-Reordering.	<–	(PDCP SDU #6)	–	–
9	Wait for 100ms (< configured t-Reordering)	–	–	–	–
10	The SS reconfigure the split DRB PDCP t-Reordering by sending an RRCConnectionReconfiguration message on Cell 1 (PCell). The UE restarts t-Reordering timer Note T₃	<—	RRCConnectionReconfiguration	–	–
11	The UE transmits an RRCConnectionReconfigurationComplete message on Cell 1 (PCell).	–>	RRCConnectionReconfigurationComplete	–	–
12	Check1: Does the UE transmit the PDCP SDU #6 via the AM RLC entity configured for SCG on Cell 10 (PSCell) after t-Reordering (750 ms) expiry? Note T₄ Check 2: Is (T₄ – T₃) > t-Reordering?	–>	(PDCP SDU #6)	3	P

7.3.7.7.3.3 Specific message contents

Table 7.3.7.7.3.3-1: RRCConnectionReconfiguration (Step 10, Table 7.3.7.7.3.2-1)

Derivation Path: 36.508, Table 4.6.1-8, condition PSCell_Add_Split_DRB

Table 7.3.7.7.3.3-2: PDCP-Config-DRB-AM (Table 7.3.7.7.3.3-1)

Derivation Path: 36.508, Table 4.8.2.1.2.2-1
Information Element	Value/remark	Comment	Condition
PDCP-Config-DRB-AM ::= SEQUENCE {
t-Reordering-r12	ms750
}