Remote communication between two sites.

[sosa2314]

Hello,

I am having an issue trying to get two control systems, roughly a mile apart, to talk to each other via the internet.

At site one I have cable internet service 173.160.x.x with a linksys E4200 router behind it.

At site two I have DSL service (due to its remote location) 65.100.x.x. It has a built in wireless router.

I am trying to create a static link or at least make the control systems talk via the internet. My boss swears this is possible with existing hardware, I am not so sure. Is there a way to make these two systems talk? Any help you all can give me is appreciated.

Thanks in Advance.

 

[Noway2]

The way to do this would be to create a VPN, which can be hardware or software based. The simplest approach in many cases would be to go with hardware. You would need two routers that have VPN support, one on each end. Companies such as Cisco and Fortigate make relatively inexpensive routers (e.g. $250-$500) that can do this. This will create a logical connection between the two devices that will share a common LAN address range and will automatically route between the two networks.

At work, we have a setup where at a remote site, a TWC connection with a Fortigate router implements a VPN connection to a public IP on our network. On one end of the VPN is a PLC and on the other is a Moore Products Procidia controller and the two communicate via Modbus TCP.

 

[sosa2314]

Understood on the VPN. I have actually tried to implement a VPN link at another site and not had it work. It was frustrating to say the least.

Is there no way to do this through routing tables on the SOHO router? Just thinking out loud. The SOHO routers are much harder to manipulate than the larger enterprise routers.

Again, thanks for your help.

 

[Noway2]

I think you really need to find a way to establish a secure connection between the sites. The alternative would be to put these devices on a public facing IP address and point them at each other. If you did that, you would have every script-kiddie and bot net banging away at your control system. How long before it becomes compromised? Your guess is as good as mine.

Some SOHO routers will support VPN functionality but brand / model X may not support the same protocols as brand model Y. Alternatively look at OpenVPN, which is a software package that can establish a secure tunnel between two networks. If you can establish the secure tunnel, then getting the devices to talk is a matter of pointing them at the remote location as the routing table should handle getting the traffic over the virtual tunnel.