Granted Patent B2

US 9,081,520 · App. 12/975,890 · Granted Jul 14, 2015

Abstract

Claims (35)

1. A system for routing a print job from a source computer coupled to a first network in a first security domain to a networked printer coupled to a second network in a second different security domain or to a networked printer server coupled to the second network, comprising:

a send platform computer in the first security domain coupled to the first network, the send platform having an output and configured to receive a print job from the source computer via the first network, to convert the received print job into a print file, and to forward the print file on the output;

a one-way data link having an input coupled to the output of the send platform computer and an output, the one-way data link configured to transfer data only from the input to the output and to prevent any signal from passing from the output to the input;

a print spooling platform computer in the second security domain coupled to the networked printer via the second network and only coupled to the send platform computer via an input coupled to the output of the one-way data link, the print spooling platform computer configured to receive the print file via the input from the one-way data link, to forward the print file as a network print job to the networked printer or to the networked printer server.

2. The system of claim 1 , wherein:

the send platform computer is configured to run a print server proxy application for converting the print job into the print file.

3. The system of claim 1 , wherein:

the print spooling platform computer is configured to run a print file capture application for forwarding the print file as a network print job to the networked printer or to the networked printer server.

4. The system of claim 1 , wherein the print spooling platform computer comprises:

a first platform configured to receive the print file from the one-way data link; and

a second platform configured to receive the print file from the first platform, and to forward the print file as a network print job to the networked printer or to the networked printer server.

5. The system of claim 4 , wherein the second platform is configured to run a print file capture application for forwarding the print file as a network print job to the networked printer or to the networked printer server.

6. The system of claim 4 , wherein the first platform using UNIX operating system and the second platform computer uses MICROSOFT WINDOWS operating system.

7. The system of claim 4 , wherein the first platform and the second platform use different operating systems.

8. The system of claim 1 , wherein the print file is transmitted across the one-way data link as a stream of segmented proprietary data packets.

9. The system of claim 1 , wherein the print file is stored in a subdirectory on the send platform computer before being transferred to the one-way data link.

10. The system of claim 1 , wherein the send platform computer monitors downloaded subdirectories for the print file to be sent across the one-way data link.

11. The system of claim 1 , wherein the print spooling platform computer monitors downloaded subdirectories for the print file to be sent to the networked printer or to the networked printer server.

12. The system of claim 1 , wherein the print spooling platform computer runs a post-processing application to transfer the print file to the networked printer or to the networked printer server.

13. The system of claim 1 , wherein the print spooling platform computer runs a TCP client application to automatically transfer the print file to the IP address of the networked printer or the networked printer server.

14. The system of claim 1 , wherein the print file is stored on the print spooling platform computer if the networked printer or the networked printer server is occupied or otherwise unavailable.

15. The system of claim 1 , wherein the send platform computer comprises a file scanning application for scanning the print file to be transferred across the one-way data link.

16. The system of claim 15 , wherein the file scanning application performs anti-virus scan on the print file.

17. The system of claim 15 , wherein the file scanning application filters on a file extension type of the print file.

18. The system of claim 15 , wherein the print file that fails the criteria of the file scanning application is quarantined.

19. The system of claim 1 , wherein the print spooling platform computer is configured to run a file scanning application for scanning the print file received from the one-way data link.

20. The system of claim 19 , wherein the file scanning application performs anti-virus scan on the print file.

21. The system of claim 19 , wherein the file scanning application filters on a file extension type of the print file.

22. The system of claim 19 , wherein the print file that fails the criteria of the file scanning application is quarantined.

23. A method for printing a print job originating at a source computer on a first network in a first security domain to a networked printer on a second network in a second different security domain or to a networked printer server on the second network, comprising the steps of:

receiving a print job from the source computer at a send platform computer in the first security domain via the first network;

converting the received print job into a print file, and then transferring the print file to an input of a one-way data link, the input of the one-way data link directly coupled to the send platform, the one-way data link having an output and configured to transfer data only from the input to the output and to prevent any signal from passing from the output to the input;

receiving the print file from the output of the one-way data link at a print spooling platform computer in the second security domain, the print spooling platform computer coupled to the send platform computer only via an input coupled to the output of the one-way data link; and

forwarding the print file as a network print job to the networked printer or to the networked printer server via the second network.

24. The method of claim 23 , wherein the steps of receiving the print file and forwarding the print file are performed on different platforms.

Assignments (8)