QCN (Qualcomm Calibration Network) is a binary file that contains all the radio configuration data for your Qualcomm chipset. Think of it as the birth certificate of your phone’s modem. It stores:

A backup of these values from a working device.

A file contains sensitive network configuration data, including IMEI and MEID numbers and network calibration values.

This is where things get technical. In modern Qualcomm devices, including the Redmi Note 7 Pro, the modem partition has strict security checks. The system checks if the IMEI stored in the QCN file matches the digital signature and hardware root of trust of the specific motherboard.