US Patent 11093627 Key provisioning

A device receives a first data item. The device stores the first data item in non-volatile memory. The device subsequently receives a second data item, where the second data item was previously generated from the first data item and a cryptographic key. The device performs a function such as, for example, an exclusive-or operation on the first data item and the second data item to generate the cryptographic key. The device uses the generated cryptographic key to encrypt data which may be transmitted over a wireless interface.