[ixfo]

Yes, CCSDS Magenta and Blue reference books mandate AES-256-GCM as a minimum for data encryption and mandate that encryption and authentication should be used, particularly for commands/uplink. Sliding scale of requirements based on application of course - your cubesat's imaging system is less critical than the flight termination system on a manned mission, for instance.

[xxpor]

Fwiw, sat c&c is the one thing you're allowed to use encryption on the Amateur radio bands for.

[adgjlsfhk1]

how is that enforceable? you can't determine what the encrypted communication is.