# US 8,068,415 B2 · Secure one-way data transfer using communication interface circuitry > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,068,415 B2 - Document ID: US8068415B2 - Status: Granted - Kind: B2 - Application number: 11/787,778 - Filed: 2007-04-18 - Published: 2008-10-23 - Granted: 2011-11-29 - Earliest claimed: 2007-04-18 - Assignees: Owl Computing Technologies, Inc. - Inventors: Ronald Mraz - Web page: https://patentgrep.com/patent/US8068415B2 ## CPC - H04L 12/5601: {Transfer mode dependent, e.g. ATM} - H04L 63/0209: {Architectural arrangements, e.g. perimeter networks or demilitarized zones} - H04L 63/162: {at the data link layer} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract Network interface circuitry for a secure one-way data transfer from a sender's computer (“Send Node”) to a receiver's computer (“Receive Node”) over a data link, such as an optical fiber or shielded twisted pair copper wire communication cable, comprising send-only network interface circuitry for transmitting data from the Send Node to the data link, and receive-only network interface circuitry for receiving the data from the data link and transmitting the received data to the Receive Node, wherein the send-only network interface circuitry is configured not to receive any data from the data link, and the receive-only network interface circuitry is configured not to send any data to the data link. The network interface circuitry may use various interface means such as PCI interface, USB connection, FireWire connection, or serial port connection for coupling to the Send Node and the Receive Node. ## Claims ### Claim 1 A method of transferring data from a Send Node to a Receive Node over an optical data link, comprising the steps of: providing a first and a second network interface circuitry; configuring said first network interface circuitry to enable data transfer from said Send Node to said optical data link, but to disable any data transfer from said optical data link to said Send Node; configuring said second network interface circuitry to enable data transfer from said optical data link to said Receive Node, but to disable any data transfer from said Receive Node to said optical data link; coupling said configured first network interface circuitry to said Send Node and a first end of said optical data link; coupling said configured second network interface circuitry to said Receive Node and a second end of said optical data link; and transferring data from said Send Node to said Receive Node over said optical data link, wherein said first network interface circuitry and said second network interface circuitry are separately administered and require independent authentication keys for communication management; said step of configuring said first network interface circuitry comprises the steps of: populating a first optical emitter and a first optical detector on a first network interface card; configuring said first optical emitter to enable data transfer from said Send Node to said optical data link; configuring said first optical detector to disable any data transfer from said optical data link to said Send Node; leaving a space on said first network interface card for a second optical emitter and a second optical detector unpopulated; and said step of configuring said second network interface circuitry comprises the steps of: populating a third optical emitter and a third optical detector on a second network interface card; configuring said third optical emitter to disable any data transfer from said Receive Node to said optical data link; configuring said third optical detector to enable data transfer from said optical data link to said Receive Node; leaving a space on said second network interface card for a fourth optical emitter and a fourth optical detector unpopulated. ### Claim 2 (depends on 1) The method of claim 1, wherein said step of coupling said configured first network interface circuitry comprises the step of using a PCI interface. ### Claim 3 (depends on 1) The method of claim 1, wherein said step of coupling said configured second network interface circuitry comprises the step of using a PCI interface. ### Claim 4 (depends on 1) The method of claim 1, wherein said step of coupling said configured first network interface circuitry comprises the step of using a USB connector. ### Claim 5 (depends on 1) The method of claim 1, wherein said step of coupling said configured second network interface circuitry comprises the step of using a USB connector. ### Claim 6 (depends on 1) The method of claim 1, wherein said step of coupling said configured first network interface circuitry comprises the step of using a FireWire connector. ### Claim 7 (depends on 1) The method of claim 1, wherein said step of coupling said configured second network interface circuitry comprises the step of using a FireWire connector. ### Claim 8 (depends on 1) The method of claim 1, wherein said step of coupling said configured first network interface circuitry comprises the step of using a serial port connector. ### Claim 9 (depends on 1) The method of claim 1, wherein said step of coupling said configured second network interface circuitry comprises the step of using a serial port connector. ### Claim 10 (depends on 1) The method of claim 1, wherein said providing step comprises the step of providing two ATM network interface cards. ### Claim 11 (depends on 10) The method of claim 10, wherein said step of providing said ATM network interface cards comprises the step of providing an ATM physical interface chip and an ATM segmentation and reassembly chip on each of said two ATM network interface cards. ### Claim 12 (depends on 1) The method of claim 1, wherein said providing step comprises the step of providing a first and a second network interface cards in form of unpopulated circuit boards. ### Claim 13 (depends on 12) The method of claim 12, wherein said providing step further comprises the step of placing silkscreen words on said unpopulated circuit boards. ### Claim 14 (depends on 1) The method of claim 1, wherein said providing step comprises the step of providing a first and a second network interface cards having a low form factor. ### Claim 15 A system for transferring data from a Send Node to a Receive Node over an optical data link, comprising: a first network interface circuitry which is configured to enable data transfer from said Send Node to said optical data link, but to disable any data transfer from said optical data link to said Send Node, and is coupled to said Send Node and a first end of said optical data link; and a second network interface circuitry which is configured to enable data transfer from said optical data link to said Receive Node, but to disable any data transfer from said Receive Node to said optical data link, and is coupled to said Receive Node and a second end of said optical data link, wherein: said first network interface circuitry and said second network interface circuitry are separately administered and require independent authentication keys for communication management; said first network interface circuitry comprises a first optical emitter and a first optical detector populated on a first network interface card; said first optical emitter is configured to enable data transfer from said Send Node to said optical data link; said first optical detector is configured to disable any data transfer from said optical data link to said Send Node; said first network interface card comprises an unpopulated space thereon for a second optical emitter and a second optical detector; said second network interface circuitry comprises a third optical emitter and a third optical detector populated on a second network interface card; said third optical emitter is configured to disable any data transfer from said Receive Node to said optical data link; said third optical detector is configured to enable data transfer from said optical data link to said Receive Node; and said second network interface card comprises an unpopulated space thereon for a fourth optical emitter and a fourth optical detector. ### Claim 16 (depends on 15) The system of claim 15, wherein said first network interface circuitry is coupled to said Send Node by a PCI interface. ### Claim 17 (depends on 15) The system of claim 15, wherein said second network interface circuitry is coupled to said Receive Node by a PCI interface. ### Claim 18 (depends on 15) The system of claim 15, wherein said first network interface circuitry is coupled to said Send Node by a USB connector. ### Claim 19 (depends on 15) The system of claim 15, wherein said second network interface circuitry is coupled to said Receive Node by a USB connector. ### Claim 20 (depends on 15) The system of claim 15, wherein said first network interface circuitry is coupled to said Send Node by a FireWire connector. ### Claim 21 (depends on 15) The system of claim 15, wherein said second network interface circuitry is coupled to said Receive Node by a FireWire connector. ### Claim 22 (depends on 15) The system of claim 15, wherein said first network interface circuitry is coupled to said Send Node by a serial port connector. ### Claim 23 (depends on 15) The system of claim 15, wherein said second network interface circuitry is coupled to said Receive Node by a serial port connector. ### Claim 24 (depends on 15) The system of claim 15, wherein each of said first network interface circuitry and said second network interface circuitry comprises an Asynchronous Transfer Mode (ATM) network interface circuit. ### Claim 25 (depends on 24) The system of claim 24, wherein said ATM network interface circuit comprises an ATM physical interface chip and an ATM segmentation and reassembly chip. ### Claim 26 (depends on 15) The system of claim 15, wherein silkscreen words indicating the send-only functionality are placed on said unpopulated space on said first network interface card. ### Claim 27 (depends on 15) The system of claim 15, wherein silkscreen words indicating the receive-only functionality are placed on said unpopulated space on said second network interface card. ### Claim 28 (depends on 15) The system of claim 15, wherein said first network interface card has a low form factor. ### Claim 29 (depends on 15) The system of claim 15, wherein said second network interface card has a low form factor.