Data diode hardware isn’t terribly expensive, but the software runs into the hundreds of thousands precisely because these are niche products.
To DIY it you need three NICs (or an optical isolator, which is honestly more work than it’s worth) because the transmitting NIC needs to see a link up before it transmits anything. That link is most easily provided by the second port on the transmitting side.
Developing software to reliably move data across the link, and ensure that it’s properly formatted etc will still be your problem.
To DIY it you need three NICs (or an optical isolator, which is honestly more work than it’s worth) because the transmitting NIC needs to see a link up before it transmits anything. That link is most easily provided by the second port on the transmitting side.
Developing software to reliably move data across the link, and ensure that it’s properly formatted etc will still be your problem.