| 摘要 |
<p>An on-line value bearing item (VBI) printing system that includes one or more cryptographic modules and a secure database is disclosed. The secure database has the ability to recover data in case of a database failure and includes account balances and other information for all of the on-line value-bearing item system customers and is capable of preventing access by unauthorized users. Also, a secure communication network is in operation to prevent unauthorized access to the users' data stored in the database. A plurality of subsystems located on the server system side of the on-line VBI system provide services related to purchasing, accounting, and printing of VBI. Preferably, these services run on multiple server machines allowing the system to be scalable. The number of the servers can easily be increased to meet the growing needs of the subsystems as the numbers of transactions and users increase. The growing number of servers will not impact the performance of the on-line postage system, because the design of the on-line postage system allows for scalability.</p> |
