US Patent 11626977 Out-of-band key splitting and key derivation

An example operation includes one or more of receiving, via a first communication channel between a sending device and a recipient device, a first partial encryption key from the receiving device, receiving, via a second communication channel between the sending device and the recipient device, a second partial encryption key from the receiving device, wherein the second communication channel comprises a different communication medium than the first communication channel, generating a transport key based on the first partial encryption key and the second partial encryption key received via the first and second channels, and encrypting data based on the generated transport key and transmitting the encrypted data to the receiving device.