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.
跨MME且SGW重选的TA更新流程
