|
3G/UMTS |
||
|
SIB Change Notification
Most UE decodes all the MIB/SIBs during cell selection. However once they decoded all the MIB/SIBs and perform registration, they may not try to decode all the SIBs. So if you change any information in SIB after UE get camped on and stay in idle mode, the UE may not recognize those changes. So there should be some mechanism for Network to explicitely tell UE to update all the SIBs.
3GPP 25.331 8.1.1.5 describes all the possible situations how SIB change should be notified and recognized by UE. The most common case of SIB change detection on UE side would be as follows :
If ( he value tag in the master information block is different from the value tag stored for this cell and this PLMN in the variable VALUE_TAG ) { }
If ( no IEs for the master information block are stored) { }
If ( he value tag in the master information block is same as the value tag stored for this cell and this PLMN in the variable VALUE_TAG ) { }
Normally this 'update request' is done by three steps (6,7,8,9) in the following sequence.
1) UE <-- NW : MIB Transmission 2) UE <-- NW : SIB Transmission 3) UE <--> NW : < Registration > 4) UE <--> NW : < Idle > 5) < Make changes in SIB > 6) UE <-- NW : MIB Transmission with changed Valuetag 7) UE <-- NW : SIB Transimssion with changed parameter 8) UE <-- NW : Paging Type 1 with bcch-Modification Info 9) UE : Decode all the SIBs again and update the changes If you have UE logging tool and check the decoded SIBs on UE side, you can easily confirm the newly decoded SIBs on UE side. If you do not have any UE logging tool, you can indirectly confirm this behavior in the following way. 1) UE <-- NW : MIB Transmission 2) UE <-- NW : SIB Transmission 3) UE <--> NW : < Registration > 4) UE <--> NW : < Idle > 5) < Make LAC changes in SIB1 : In this test, I changed LAC from 0 to 1> 6) UE <-- NW : MIB Transmission with changed Value tag 7) UE <-- NW : SIB Transimssion with changed parameter 8) UE <-- NW : Paging Type 1 with bcch-Modification Info 9) UE : Decode all the SIBs again and update the changes 10) < UE should go through following process for Location Updating for new LAC > 12) UE <--> NW : < RRC Connection Setup > 13) UE <--> NW : < Perform Location Area Updating > 14) UE <--> NW : < Perform Routing Area Updating > 15) UE <--> NW : < RRC Connection Release > 16) UE <--> NW : < Idle >
1) UE <-- NW : MIB Transmission MasterInformationBlock mib-ValueTag: 1 plmn-Type: gsm-MAP (0) gsm-MAP plmn-Identity mcc: 3 items Item 0 Digit: 0 Item 1 Digit: 0 Item 2 Digit: 1 mnc: 2 items Item 0 Digit: 0 Item 1 Digit: 1 sibSb-ReferenceList: 5 items Item 0 SchedulingInformationSIBSb sibSb-Type: sysInfoType1 (0) sysInfoType1: 1 scheduling scheduling sib-Pos: rep32 (3) rep32: 2 Item 1 SchedulingInformationSIBSb sibSb-Type: sysInfoType3 (2) sysInfoType3: 1 scheduling scheduling sib-Pos: rep32 (3) rep32: 3 Item 2 SchedulingInformationSIBSb sibSb-Type: sysInfoType5 (4) sysInfoType5: 1 scheduling scheduling segCount: 4 sib-Pos: rep64 (4) rep64: 5 sib-PosOffsetInfo: 3 items Item 0 SibOFF: so2 (0) Item 1 SibOFF: so2 (0) Item 2 SibOFF: so28 (13) Item 3 SchedulingInformationSIBSb sibSb-Type: sysInfoType7 (6) sysInfoType7: NULL scheduling scheduling sib-Pos: rep64 (4) rep64: 10 Item 4 SchedulingInformationSIBSb sibSb-Type: sysInfoType11 (10) sysInfoType11: 1 scheduling scheduling segCount: 9 sib-Pos: rep128 (5) rep128: 11 sib-PosOffsetInfo: 8 items Item 0 SibOFF: so4 (1) Item 1 SibOFF: so2 (0) Item 2 SibOFF: so2 (0) Item 3 SibOFF: so22 (10) Item 4 SibOFF: so2 (0) Item 5 SibOFF: so4 (1) Item 6 SibOFF: so2 (0) Item 7 SibOFF: so2 (0)
2) UE <-- NW : SIB Transmission
: I will list only one SIB that will be changed later. In real test, several other SIBs are transmitted as well. SysInfoType1 cn-CommonGSM-MAP-NAS-SysInfo: 0000 CN Common GSM-MAP NAS system information Location Area Code (LAC): 0x0000 (0) cn-DomainSysInfoList: 2 items Item 0 CN-DomainSysInfo cn-DomainIdentity: ps-domain (1) cn-Type: gsm-MAP (0) gsm-MAP: 8001 PS domain specific system information Routing Area Code (RAC): 0x80 (128) 0000 00.. = Spare bit(s): 0 .... ..0. = NMO I: Network Mode of Operation indicated in Bit 1 (NMO) is used for MS configured for NMO_I_Behaviour .... ...1 = NMO: Network Mode of Operation II cn-DRX-CycleLengthCoeff: 8 Item 1 CN-DomainSysInfo cn-DomainIdentity: cs-domain (0) cn-Type: gsm-MAP (0) gsm-MAP: 0001 CS domain specific system information T3212: 0 0000 000. = Spare bit(s): 0 .... ...1 = ATT: MSs shall apply IMSI attach and detach procedure cn-DRX-CycleLengthCoeff: 8 ue-ConnTimersAndConstants t-305: noUpdate (0) t-308: ms320 (3) t-314: s0 (0) t-315: s0 (0) t-316: s-inf (6) t-317: infinity1 (1) ue-IdleTimersAndConstants t-300: ms2000 (10) n-300: 5 t-312: 10 n-312: s1 (0)
6) UE <-- NW : MIB Transmission with changed Valuetag MasterInformationBlock mib-ValueTag: 2 plmn-Type: gsm-MAP (0) gsm-MAP plmn-Identity mcc: 3 items Item 0 Digit: 0 Item 1 Digit: 0 Item 2 Digit: 1 mnc: 2 items Item 0 Digit: 0 Item 1 Digit: 1 sibSb-ReferenceList: 5 items Item 0 SchedulingInformationSIBSb sibSb-Type: sysInfoType1 (0) sysInfoType1: 2 scheduling scheduling sib-Pos: rep32 (3) rep32: 2 Item 1 SchedulingInformationSIBSb sibSb-Type: sysInfoType3 (2) sysInfoType3: 1 scheduling scheduling sib-Pos: rep32 (3) rep32: 3 Item 2 SchedulingInformationSIBSb sibSb-Type: sysInfoType5 (4) sysInfoType5: 1 scheduling scheduling segCount: 4 sib-Pos: rep64 (4) rep64: 5 sib-PosOffsetInfo: 3 items Item 0 SibOFF: so2 (0) Item 1 SibOFF: so2 (0) Item 2 SibOFF: so28 (13) Item 3 SchedulingInformationSIBSb sibSb-Type: sysInfoType7 (6) sysInfoType7: NULL scheduling scheduling sib-Pos: rep64 (4) rep64: 10 Item 4 SchedulingInformationSIBSb sibSb-Type: sysInfoType11 (10) sysInfoType11: 1 scheduling scheduling segCount: 9 sib-Pos: rep128 (5) rep128: 11 sib-PosOffsetInfo: 8 items Item 0 SibOFF: so4 (1) Item 1 SibOFF: so2 (0) Item 2 SibOFF: so2 (0) Item 3 SibOFF: so22 (10) Item 4 SibOFF: so2 (0) Item 5 SibOFF: so4 (1) Item 6 SibOFF: so2 (0) Item 7 SibOFF: so2 (0)
7) UE <-- NW : SIB Transimssion with changed parameter SysInfoType1 cn-CommonGSM-MAP-NAS-SysInfo: 0001 CN Common GSM-MAP NAS system information Location Area Code (LAC): 0x0001 (1) cn-DomainSysInfoList: 2 items Item 0 CN-DomainSysInfo cn-DomainIdentity: ps-domain (1) cn-Type: gsm-MAP (0) gsm-MAP: 8001 PS domain specific system information Routing Area Code (RAC): 0x80 (128) 0000 00.. = Spare bit(s): 0 .... ..0. = NMO I: Network Mode of Operation indicated in Bit 1 (NMO) is used for MS configured for NMO_I_Behaviour .... ...1 = NMO: Network Mode of Operation II cn-DRX-CycleLengthCoeff: 8 Item 1 CN-DomainSysInfo cn-DomainIdentity: cs-domain (0) cn-Type: gsm-MAP (0) gsm-MAP: 0001 CS domain specific system information T3212: 0 0000 000. = Spare bit(s): 0 .... ...1 = ATT: MSs shall apply IMSI attach and detach procedure cn-DRX-CycleLengthCoeff: 8 ue-ConnTimersAndConstants t-305: noUpdate (0) t-308: ms320 (3) t-314: s0 (0) t-315: s0 (0) t-316: s-inf (6) t-317: infinity1 (1) ue-IdleTimersAndConstants t-300: ms2000 (10) n-300: 5 t-312: 10 n-312: s1 (0)
8) UE <-- NW : Paging Type 1 with bcch-Modification Info
message: pagingType1 (0) pagingType1 bcch-ModificationInfo mib-ValueTag: 2
|
||