Network Hardware

I am trying to connect 3 ignition sites over the internet. All of the sites
are using a Comcast business class router. I need the computers that
are connected to think that they are on the same physical network for
the Inductive to work as I am expecting (I tested this on the bench hardwired).
Does anyone have any suggested hardware to create a VPN link between the

I can’t recommend any specific hardware, but I do this myself with Linux routers running OpenVPN and bridge-utils and vconfig. I have a cloud server as the OpenVPN endpoint and it contains some bare software bridges, one for each VLAN I want to span any of my sites. At each site, I have a software bridge for each of its VLANs. Finally, I have OpenVPN up/down scripts that create and destroy GRE tap connections from bridge to bridge.
I find this very handy when I’m working from home with PLC lab gear in the office.

Its all about your network hardware and capabilities, but your correct a site to site VPN is the easiest way to go. Prob not something your going to setup in the comcast router, but your office router behind the comcast one. I have been getting hooked on Ubiquiti stuff lately ( nice gear with a ton of features for a relative low cost.