学习笔记二四：TA更新流程

原文来源

笔记内容来自：51学通信

2017开始时长超20分钟的长课程视频

EPC信令之：跨MME且SGW重选的TA更新流程(2017新版)

笔记内容

思维导图

场景说明

TA更新流程

TA更新触发条件

A stand-alone tracking area update (with or without S‑GW change, described in clauses 5.3.3.1 and 5.3.3.2 respectively) occurs when a GPRS-attached or E‑UTRAN-attached UE experiences any of the following conditions:

- UEdetects it has entered a new TA that is not in the list of TAIs that the UEregistered with the network (except for the case of a UE configured to performAttach with IMSI when entering a TA in a new non-equivalent PLMN in RRC-IDLEmode);

- theperiodic TA update timer has expired;

- UE wasin UTRAN PMM_Connected state (e.g. URA_PCH) when it reselects to E‑UTRAN;

- UE wasin GPRS READY state when it reselects to E‑UTRAN;

- the TINindicates "P-TMSI" when the UE reselects to E-UTRAN (e.g. due tobearer configuration modifications performed on GERAN/UTRAN);

- the RRCconnection was released with release cause "load re-balancing TAUrequired";

- the RRClayer in the UE informs the UE's NAS layer that an RRC connection failure (ineither E-UTRAN or UTRAN) has occurred;

- achange of the UE Network Capability and/or MS Network Capability and/or UESpecific DRX Parameters and/or TS 24.008 [47] MS Radio Accesscapability (e.g. due to GERAN radio capability change, E-UTRAN, NG-RANcapability change or cdma2000 Radio Access Technology Capability change)information of the UE.

- for UEsupporting RACS in ECM-IDLE as defined in clause 5.11.3a, a change in UERadio Access capability (e.g. due to GERAN radio capability change, E-UTRAN,NG-RAN capability change or cdma2000 Radio Access Technology Capability change)corresponding to signalling a different UE Radio Capability ID.

- achange in conditions in the UE require a change in the extended idle mode DRXparameters previously provided by the MME.

- for aUE supporting CS fallback, or configured to support IMS voice, or both, achange of the UE's usage setting or voice domain preference for E-UTRAN.

- for aSR-VCC capable UE, a change of MS Classmark 2 and/or MS Classmark 3 and/or SupportedCodecs.

- UEmanually selects a CSG cell whose CSG ID and associated PLMN is absent fromboth the UE's Allowed CSG list and the UE's Operator CSG list.

- UEreceives a paging request from the MME while the Mobility Management back offtimer is running and the UE's TIN indicates "P-TMSI".

- achange in any of the values of information included in Preferred NetworkBehaviour as defined in clause 4.3.5.10 that would create incompatibilitywith the Supported Network Behaviour provided by the serving MME.