This is a crude network drawing of what I’m wanting to accomplish.

I do a lot of work on industrial equipment that uses its own subnet. Most of these subnets are very isolated from outside networks and internet access. Most of the time I end up having to reconfigure my Ethernet adapter and plug directly into the machine while using my phone’s hotspot to access my network drives.

What I want is to be able to build a small box with a managed switch or something that’ll make this process a little easier. The idea is that I would be able to show up on site and

1. Run a cable from their machine to my “yellow” port. Most of these machine networks don’t have DHCP, so I would need my switch (or whatever hardware I end up using) to find an unused ip address and use that.

2. Run a cable from an internet source (sometimes the customer has an internet drop, or I could use a dedicated hotspot) to my “blue” port. Whatever hardware I’m using in my box needs to have a pretty solid firewall between yellow and green.

3. Then connect my laptop to my “green” network. I should then be able to have direct access to anything on the “yellow” network and also be able to pull files from my cloud drives. This network should stay pretty static, at most I may have 2-3 other laptops on it and may start carrying around a NAS for larger projects.

I think this involves a firewall, managed switch, and or a NAT. I’m not super strong on networking skills, but I know enough that if y’all can give any broad stroke suggestions with the right technical terms, I can probably hobble myself through it.

TIA!