Synergy over a serial connection?

Synergy is a well known tool to have only one keyboard and mouse for two networked (TCP/IP) computers with a screen each. I loved to use it at my former job. Now, at my new job, I've still got two PC, but they are in completely different and isolated networks: Administrative and development, Windows and Linux, accordingly.

Seeing a "serial" feature of putty (Windows), which usually is able to do all sorts of tunneling, I wonder whether it would allow me to use Synergy through a TCP-over-Serial connection. I reckon I'd need to use SLIP on the Linux side.

Has anyone got experience with this, or with parts of this?

If you're running SLIP (or, better, PPP), then you've built an IP network over your serial cable. You assign IP addresses (RFC 1918 private addresses most likely) on both sides, and use Synergy with those addresses. There wouldn't be any reason to use PuTTY's port forwarding.

Of course, your two networks are no longer isolated. Especially if you keep routing/forwarding turned off on both machines this may be OK or may not be, depending on your security policies and needs.

Do these machines have to be isolated? What about adding secondary NICs to both machines and then putting them both on a private network (10.10.1.x). Make sure that no traffic is routed through that network.

Another simpler option might just be to purchase a KVM and just use it for K&M.

Here is synergy-through-usb https://github.com/iHateInventNames/synergy-through-usb

It allows to use usb2usb cable.