Performing cryptographic operations without ensuring that the supporting inputs are ready to supply valid data may compromise the cryptographic result.
Many cryptographic hardware units depend upon other hardware units to supply information to them to produce a securely encrypted result. For example, a cryptographic unit that depends on an external random-number-generator (RNG) unit for entropy must wait until the RNG unit is producing random numbers. If a cryptographic unit retrieves a private encryption key from a fuse unit, the fuse unit must be up and running before a key may be supplied.
Best practices should be used to design cryptographic systems.
Continuously ensuring that cryptographic inputs are supplying valid information is necessary to ensure that the encrypted output is secure.