Introduction

From manufacturing work orders to customer invoices and paychecks, these Hewlett Packard LaserJet printers now output an array of critical documents. Of course, as the importance of the documents output by these printers increases, so does the need for greater printer security and accountability. Capella Technologie’s SecureDIMM™ is a hardware-based solution that addresses this need.

In the event that a file can not be printed immediately due to network traffic or printer status (for instance, “printer off-line” or “printer out of paper”), client application output is stored or queued in print spool files on either the client system or network print server. These spool files can be “cracked” with simple text editors making the data vulnerable to unauthorized duplication, perusal and modification.

Application output data encryption, can minimize the effects of tampering by making the data unviewable. Once the data leaves the host it can be encrypted and with the Decryption Option it can be de-encrypted at the printer.

The Decryption option provides sophisticated hardware-based data decryption capabilities that are built into the firmware on the DIMM, where they can be activated by a special printer escape code.

Because the decryption takes place in the printer hardware just prior to the output being generated it makes the data stream less vulnerable to unauthorized access while still providing access to other printer enhancements such as optional printer fonts and languages.

In the absence of a decryption escape code, the printer continues to function like any other LaserJet printer, providing maximum investment efficiency. For maximum security applications, however, the DIMM can be configured so that the printer will only output encrypted data. This feature could prove useful in payroll and other check writing applications.

In its appearance and installation, the SecureDIMM closely resembles a standard HP LaserJet memory DIMM. Indeed, its pin configuration is analogous to a standard DIMM, making it compatible with all recent DIMM-based HP LaserJet printers.

The SecureDIMM occupies a single memory socket, leaving any additional sockets available for printer memory upgrades. It was engineered to offer full LaserJet compatibility, so it can coexist with other printer personalities, including Postscript language support. This design also offers compatibility with most standard software applications.

Although the Capella SecureDIMM looks somewhat like a standard DIMM, in its cons-