我們的終端進(jìn)入LRP mode之后，大約9個(gè)半小時(shí)后會被網(wǎng)絡(luò)側(cè)去附著，QXDM log顯示網(wǎng)絡(luò)側(cè)的去附著類型（type_of_detach）為2, reattach not required.
T3312等于180分鐘。3次路由區(qū)更新后，再過30分鐘，網(wǎng)絡(luò)側(cè)發(fā)detach request 給終端。

99 2016-04-01 18:01:12:140 2016-04-01 18:01:12:472 路由區(qū)更新 成功
100 2016-04-01 21:01:13:638 2016-04-01 21:01:13:801 路由區(qū)更新 成功
101 2016-04-02 00:01:14:945 2016-04-02 00:01:15:178 路由區(qū)更新 成功
102 2016-04-02 00:31:13:679 2016-04-02 00:31:13:859 網(wǎng)絡(luò)觸發(fā)的業(yè)務(wù)請求 成功

聯(lián)通給的解釋是因?yàn)榻K端進(jìn)入LPR mode后長時(shí)間不發(fā)數(shù)據(jù)到網(wǎng)絡(luò)側(cè)，所以被網(wǎng)絡(luò)側(cè)去附著。
但是為何會是 reattach not required?

根據(jù)23.401規(guī)范，Detach共有4種情況，其分別是為：

- UE-Initiated Detach Procedure. In the ISR activated case the UE initiated detach is split into two sub procedures,
one for UE camping on E-UTRAN and one for UE camping on GERAN/UTRAN;
- MME-Initiated Detach Procedure;
- SGSN-Initiated Detach procedure with ISR activated;
- HSS-Initiated Detach Procedure.

樓主反映的情況應(yīng)該是第二種情況v