Computer question - setting up a VPN - PeachParts Mercedes-Benz Forum

cornblatt · #1 05-09-2011, 05:13 PM

I have a question for you computer networking experts out there...

I have 3 pieces of industrial equipment that are networked together. They need to be monitored remotely over the internet. The location in which they are installed does not have a dedicated wired internet connection but has access to a building-wide public wireless network.

I don't want these 3 industrial devices to be able to access the internet, get viruses, etc. What I want is to be able to remotely connect my PC as another node on their private network (over the internet), monitor them, and then disconnect. I'm not in the same building - I'm miles away.

My initial thought was to use:
1) a VPN router, either with some sort of client software on my PC, or a matching router at my end, whatever is necessary, AND
2) a wireless bridge (to connect the VPN router to the public wireless network)

Here is a drawing of what I was picturing:

Code:

REMOTE LOCATION:
              .----------.
[Device 1]----+          |     .----------.                        .-----.
              |  VPN     |     | Wireless |        public          |     |
[Device 2]----+  Router  +-----+ Bridge   +-) ) ) -wireless- ( ( (-+  ?  +---< INTERNET
              |          |     | Linksys  |        network         |     |
[Device 3]----+          |     | WET610N  |                        '-----' 
              '----------'     '----------'

AT MY OFFICE:
              .------------.     .----------.
              | Cable      |     | Firewall |
INTERNET >----+ Modem      +-----+ Router   +-----[ My Computer ]
              | Dynamic IP |     |          |
              '------------'     '----------'

But, I am a bit uncertain as to whether this would work. Specifically, I don't know how to be certain that the VPN traffic will pass through the miscellaneous (unknown) devices in the public wireless network. I also don't know how I would connect to the VPN router remotely (since it's behind the wireless router (marked with ? in the drawing) and bridge, I don't think it would have an IP address that I could access from the internet). And, I want to make sure that the 3 pieces of industrial equipment can't see the internet.

I've been reading manuals for VPN routers all day but I'm not really seeing how to configure them to implement something like this.

I could probably convince the appropriate people to make some minor changes to the configuration of the building wireless network if necessary, but I'd need to be certain of what had to be done before I ask.

If anyone has any pointers/suggestions on this, I would be very appreciative!