LTE中attach和TAU流程（参考）.ppt

Combined attach：联合EPS附着流程用于工作在CS/PS mode1或者CS/PS mode2的UE请求EPS和non-EPS服务。 联合EPS附着流程也用于工作于。。。的UE在已经附着到non-EPS服务的情况下附着到EPS服务。 在这种情况下，UE应该启动EPS attach type IE为“combined EPS/IMSI attach”的联合EPS附着流程。 * 为了在E-UTRAN的覆盖范围内指出UE的specific DRX参数，UE需向网络侧发送一个在DRX 参数IE 中包含UE specific DRX参数的TRACKING AREA UPDATE REQUEST消息（除非UE在GRRAN或UTRAN覆盖方位内已经指出了它的DRX参数）。在这种情况下，当UE进入E-UTRAN覆盖范围并启动一个TAU规程时，UE不应在消息中包含相关DRX参数。 当在S1 mode的UE启动一个TAU流程时，UE应使用current EPS NAS 安全密钥来对TRACKING AREA UPDATE REQUEST消息进行完整性保护。 如果UE有数据等待传输并且执行一个S101 mode 到S1 mode 的inter-system change（to 在UE储存的TAI list中的TA），UE应执行一个服务请求规程而不是TAU规程。 * Values “TA updated and ISR activated” and “combined TA/LA updated and ISR activated” are used only for a UE supporting also A/Gb or Iu mode. Idle state Signalling Reduction (ISR) 是在同时可以接入E-UTRAN和ERAN/UTRAN的区域内，为了减少UE频繁在E-UTRAN和ERAN/UTRAN间切换产生的信令而设计的。ISR启动后，网络（MME和SGSN）和UE均备份两套MM上下文。Idle状态下，UE在E-UTRAN和ERAN/UTRAN之间重选是不需要和网络有信令交互的。当PDN寻呼终端时，MME和SGSN分别在TA和RA上寻呼UE，UE在哪个网络上应答，就从那个接入网接入。 ESM中： EPS bearer context deactivation procedure 由网络侧发起，去激活EPS承载。也作为UE发起的断开PDN连接的响应。 在没有NAS连接时，MME直接本地去激活，不必和UE进行信令交互。在重新进入CONNECTED态时，可通过ServiceRequest和TAU同步承载。  * Cause #2 – IMSI unknown in HSS This EMM cause is sent to the UE if the UE is not known (registered) in the HSS. This EMM cause does not affect operation of the EPS service, although is may be used by an EMM procedure. Cause #3 – Illegal UE This EMM cause is sent to the UE when the network refuses service to the UE either because an identity of the UE is not acceptable to the network or because the UE does not pass the authentication check, i.e. the RES received from the UE is different from that generated by the network. Cause #6 – Illegal ME This EMM cause is sent to the UE if the ME used is not acceptable to the network, e.g. blacklisted. Cause #9 – UE identity cannot be derived by the network. This EMM cause is sent to the UE when the network cannot derive the UEs identity from the GUTI/S-TMSI/P-TMSI and RAI e.g. no m