LTE device can operate in NV mode, where all parameters are stored on the AT, or they can be configured to operate in Card mode, where all parameters are stored on the UICC card. By default the parameters are stored in UICC cards. But we can configure AT to operate in NV mode, then we can change A-key, SCM, MOB_TERM, SCI etc using QPST or UDM.
Following is how to switch between NV mode and Card mode: 1. In QPST, open the Service Programming menu and select the 1x/HDR Security tab. 2. Go to R-UIM config. 3. To operate in Card mode, select the R-UIM only option from the drop-down menu. 4. To operate in NV mode, select the NV only option from the drop-down menu. (You may need remove the UICC card from device to complete this setting) 5. Click WRITE TO PHONE.