| 摘要 |
Methods of verifying use of postage charges in respect of mail items are disclosed. An authentication code is derived from a secret identification of a sender and a part of the destination address of the item. The code is printed on the mail item together with a sender account reference. On receipt of the mail item, the postal authority is able to use the account reference to access the secret identification and thereby determine if the destination address derived corresponds to that printed on the mail to verify the payment for the postage charge. In a modification, each time a postage meter effects a transaction with a remote center, the remote center generates and transmits to the meter a transaction number. The meter utilises a unique key to generate an encrypted code based on an item count and the transaction number. The code and a meter identification are printed on the mail. The postal authority reads the meter identification to access the unique key to decrypt the code and then compares the current transaction number with the transaction number derived from the code in order to verify the postage charges used by the sender.
|
