Is there such a thing as a disk drive that can be on two separate networks simultaneously?

Can some kind of disk drive exist on two separate computer networks, so that files can be written from one and then read from the other? But, it would have to be unable to do anything else that might facilitate a hacker bridge between the two networks. So, the ONLY thing you could do with it is manually pass files between the two networks.


That doesn’t sound any different from a network linkage limited to reading and writing files.

I don’t know if network drives these days commonly come with two independent ethernet ports, but it’s pretty trivial to set up a PC with two network interfaces to act as a disk server. You just have to make sure you don’t set the PC up to bridge the networks.

Any network file system server (NAS device) provided with two network interfaces should work. It would be unusual to configure such a system to act as a router, so the default config should match your requirements. Then you simply configure the access rights on the server to match the requirements.

As TriPolar says, a router that brides two networks could be configured to only pass traffic that is destined to a specific service on a specific machine, and thus a server could be placed on one network and made visible on the other via the restricted router settings.

If you assume that the network that has read only rights is the insecure side, and the write capable side is more secure, both solutions have pretty much equal merit. If you want a more symmetric solution the first one is probably more useful. But there is devil in the exact details.

If you’re truly paranoid, check out the “data diode” offerings from various vendors:

I’m not really paranoid, but I am under control of those who might be. I’m interested in hardware that CANNOT be set up to do more than what I discribe.

The data diode is neat…