Abstract: In a digital copier, wherein hard-copy original images are scanned and retained as digital data in a memory and subsequently digitally printed out as copies, original data is encrypted before being stored in the memory, and then decrypted incidental to printing or other export. Data stored within a digital copier is thus protected from being hacked or otherwise accessed. Keys for encryption or decryption are stored external to the copier. Properties of “Pretty Good Privacy” (PGP), such as the use of session keys, can be employed. Also, an independent arbiter, connected with a plurality of copiers over a network, can perform security functions, such as retaining decryption keys for a large number of copy jobs, or erasing or transferring data out of copiers in response to a security alert.

Abstract: In a digital copier, wherein hard-copy original images are scanned and retained as digital data in a memory and subsequently digitally printed out as copies, original data is encrypted before being stored in the memory, and then decrypted incidental to printing or other export. Data stored within a digital copier is thus protected from being hacked or otherwise accessed. Keys for encryption or decryption are stored external to the copier. Properties of “Pretty Good Privacy” (PGP), such as the use of session keys, can be employed. Also, an independent arbiter, connected with a plurality of copiers over a network, can perform security functions, such as retaining decryption keys for a large number of copy jobs, or erasing or transferring data out of copiers in response to a security alert.