Identifying a specific combination of metering accounting vault and digital printer

摘要

For preventing monitoring of postage indicia data which is sent from a postage metering vault to a remotely located digital printer (21) over a communication link (C11) between the meter vault and the digital printer (21), the meter (11) is provided with an encryption engine (37) for encrypting postage indicia data utilizing an encryption key. The digital printer (21) includes a decryption engine (53) for decrypting postage data received from said meter (11) utilizing the same encryption key and then prints a postage indicia pursuant to the decrypted postage indicia data. The postage meter (11) also includes a key manager (39) for generating new encryption key pursuant to a token which is either randomly generated or generated pursuant to an algorithm by a similar encryption key manager (61) located in the digital printer (21), which token is also used to generate the decryption key for the decryption engine (53). As a result, the encryption keys are the same. Upon power-up of the system or at such other preselected times, the print controller module of the digital printer (21) sends out an encrypted message to the meter (11). The message consist of a random number. The encryption/decryption engine (37) of the vault decrypts the message. The vault then returns an encrypted new message to the print controller (23) which includes an encoded representation of the relationship of the two messages. Upon receiving the new message from the vault, the print controller (23) decrypts the new message and verifies the relationship. The print controller (23) is then enabled to print a postage indicia. <IMAGE>