5.3.14 Unified Access Control

38.3313GPPNRProtocol specificationRadio Resource Control (RRC)Release 17TS

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

5.3.14.1 General

The purpose of this procedure is to perform access barring check for an access attempt associated with a given Access Category and one or more Access Identities upon request from upper layers according to TS 24.501 [23] or the RRC layer. This procedure does not apply to IAB-MT. This procedure does not apply to L2 U2N Relay UE initiating RRC connection establishment or RRC connection resume upon reception of any message from a L2 U2N remote UE via SL-RLC0 or SL-RLC1 in accordance to 5.3.3.1a or 5.3.13.1a.

After a PCell change in RRC_CONNECTED the UE shall defer access barring checks until it has obtained SIB1 (as specified in 5.2.2.2) from the target cell.

5.3.14.2 Initiation

Upon initiation of the procedure, the UE shall:

1> if timer T390 is running for the Access Category:

2> consider the access attempt as barred;

1> else if timer T302 is running and the Access Category is neither ‘2’ nor ‘0’:

2> consider the access attempt as barred;

1> else:

2> if the Access Category is ‘0’:

3> consider the access attempt as allowed;

2> else:

3> if SIB1 includes uac-BarringPerPLMN-List that contains a UAC-BarringPerPLMN for the selected PLMN or SNPN:

4> if the procedure in 5.2.2.4.2 for a selected PLMN resulted in use of information in npn-IdentityInfoList and UAC-BarringPerPLMN has an entry with the plmn-IdentityIndex corresponding to used information in this list:

5> select the UAC-BarringPerPLMN entry with the plmn-IdentityIndex corresponding to used information in the npn-IdentityInfoList;

4> else:

5> select the UAC-BarringPerPLMN entry with the plmn-IdentityIndex corresponding to the selected PLMN and the PLMN-IdentityInfo, if any, or the selected SNPN and the npn-IdentityInfoList;

3> if any UAC-BarringPerPLMN entry is selected:

4> in the remainder of this procedure, use the selected UAC-BarringPerPLMN entry (i.e. presence or absence of access barring parameters in this entry) irrespective of the uac-BarringForCommon included in SIB1;

3> else if SIB1 includes uac-BarringForCommon:

4> in the remainder of this procedure use the uac-BarringForCommon (i.e. presence or absence of these parameters) included in SIB1;

3> else:

4> consider the access attempt as allowed;

3> if uac-BarringForCommon is applicable or the uac-ACBarringListType indicates that uac-ExplicitACBarringList is used:

4> if the corresponding UAC-BarringPerCatList contains a UAC-BarringPerCat entry corresponding to the Access Category:

5> select the UAC-BarringPerCat entry;

5> if the uac-BarringInfoSetList contains a UAC-BarringInfoSet entry corresponding to the selected uac-barringInfoSetIndex in the UAC-BarringPerCat:

6> select the UAC-BarringInfoSet entry;

6> perform access barring check for the Access Category as specified in 5.3.14.5, using the selected UAC-BarringInfoSet as "UAC barring parameter";

5> else:

6> consider the access attempt as allowed;

4> else:

5> consider the access attempt as allowed;

3> else if the uac-ACBarringListType indicates that uac-ImplicitACBarringList is used:

4> select the uac-BarringInfoSetIndex corresponding to the Access Category in the uac-ImplicitACBarringList;

4> if the uac-BarringInfoSetList contains the UAC-BarringInfoSet entry corresponding to the selected uac-BarringInfoSetIndex:

5> select the UAC-BarringInfoSet entry;

5> perform access barring check for the Access Category as specified in 5.3.14.5, using the selected UAC-BarringInfoSet as "UAC barring parameter";

4> else:

5> consider the access attempt as allowed;

3> else:

4> consider the access attempt as allowed;

1> if the access barring check was requested by upper layers:

2> if the access attempt is considered as barred:

3> if timer T302 is running:

4> if timer T390 is running for Access Category ‘2’:

5> inform the upper layer that access barring is applicable for all access categories except categories ‘0’, upon which the procedure ends;

4> else

5> inform the upper layer that access barring is applicable for all access categories except categories ‘0’ and ‘2’, upon which the procedure ends;

3> else:

4> inform upper layers that the access attempt for the Access Category is barred, upon which the procedure ends;

2> else:

3> inform upper layers that the access attempt for the Access Category is allowed, upon which the procedure ends;

1> else:

2> the procedure ends.

5.3.14.3 Void

5.3.14.4 T302, T390 expiry or stop (Barring alleviation)

The UE shall:

1> if timer T302 expires or is stopped:

2> for each Access Category for which T390 is not running:

3> consider the barring for this Access Category to be alleviated:

1> else if timer T390 corresponding to an Access Category other than ‘2’ expires or is stopped, and if timer T302 is not running:

2> consider the barring for this Access Category to be alleviated;

1> else if timer T390 corresponding to the Access Category ‘2’ expires or is stopped:

2> consider the barring for this Access Category to be alleviated;

1> when barring for an Access Category is considered being alleviated:

2> if the Access Category was informed to upper layers as barred:

3> inform upper layers about barring alleviation for the Access Category.

2> if barring is alleviated for Access Category ‘8’; or

2> if barring is alleviated for Access Category ‘2’:

3> perform actions specified in 5.3.13.8;

5.3.14.5 Access barring check

The UE shall:

1> if one or more Access Identities equal to 1, 2, 11, 12, 13, 14, or 15 are indicated according to TS 24.501 [23], and

1> if for at least one of these Access Identities the corresponding bit in the uac-BarringForAccessIdentity contained in "UAC barring parameter" is set to zero:

2> consider the access attempt as allowed;

1> else:

2> if the establishment of the RRC connection is the result of release with redirect with mpsPriorityIndication (either in NR or E-UTRAN); and

2> if the bit corresponding to Access Identity 1 in the uac-BarringForAccessIdentity contained in the "UAC barring parameter" is set to zero:

3> consider the access attempt as allowed;

2> else if Access Identity 3 is indicated:

3> draw a random number ‘rand‘ uniformly distributed in the range: 0 ≤ rand < 1;

3> if ‘rand‘ is lower than the value indicated by uac-BarringFactorForAI3 included in "UAC barring parameter":

4> consider the access attempt as allowed;

3> else:

4> consider the access attempt as barred;

2> else:

3> draw a random number ‘rand‘ uniformly distributed in the range: 0 ≤ rand < 1;

3> if ‘rand‘ is lower than the value indicated by uac-BarringFactor included in "UAC barring parameter":

4> consider the access attempt as allowed;

3> else:

4> consider the access attempt as barred;

1> if the access attempt is considered as barred:

2> draw a random number ‘rand‘ that is uniformly distributed in the range 0 ≤ rand < 1;

2> start timer T390 for the Access Category with the timer value calculated as follows, using the uac-BarringTime included in "UAC barring parameter":

T390 = (0.7+ 0.6 _* rand) _* uac-BarringTime.