Device providing encryption services for Internet fax machines

摘要

The invention provides an encryption device 1 which enables a client (e.g. Internet facsimile machines 2, 2') to easily use encrypted electronic mail without having to perform key and certification management and without having to perform encryption/decryption. When an Internet facsimile machine 2 transmits electronic mail (a), the electronic device converts the received email into encrypted mail (b) and transmits it to a mail server 3 for onwards transmission. The device also performs decryption for incoming e-mails. When another Internet facsimile machine 2' transmits data (c) including a part to be encrypted and transmission destination information as a main body of mail to the encryption device, the device encrypts the main body of the mail under a prescribed encryption method and returns it (d) to the facsimile machine 2'. The facsimile machine then formats the returned data into encrypted mail and transmits it (e) to a remote Internet fax machine 6. Public key encryption is disclosed and the encryption device may also generate signatures. In another embodiment, an encryption/decryption URL is provided to the encryption device.