Canon LBP7780CX User Manual page 719

3
Select [Signature Algorithm].
Select from [SHA1], [SHA256], [SHA384], or [SHA512].
4
Select [Key Algorithm].
Select from [512 bit], [1024 bit], [2048 bit], or [4096 bit].
When you select [SHA384] and [SHA512] in [Signature Algorithm], you can create a key only when selecting other than
[512 bit].
NOTE
Key Generation Algorithm