Device connection through cellular modem

General Discussion
1

I got a project to connect an Ignition Gateway to a Scadapack 334. They had configured the gateway to connect with the DNP3 driver and the Modbus TCP driver.

The Scadapack is mounted in a mobile skid that will be deployed in a remote location and will need a cellular modem to get internet access.
I have configured the Scadapack with an IP address xxx.xxx.x.x subnet 255.255.255.0 and gateway xxx.xxx.x.y
The modem has the LAN IP address set to xxx.xxx.x.y
I have the modem set on a public APN.

The gateway is set to connect to the Scadapack IP address xxx.xxx.x.x for both drivers. The modbus tcp driver is set to port 502 and the dnp3 driver is set to port 20000.

So the problem is that I can't get the gateway to connect to scadapack over the internet. However when I bypass the cell modem by connecting the laptop hosting the gateway directly to the ethernet switch on the skid both drivers connect and I get the tag data.

My question is what setting or configuration do I need to change to get the cell modem to work with my Ignition gateway so I can connect to the Scadapack?

Thanks

2

Many times the public IP you are given by the ISP/cell service provider isn't a public IP that you can pass through directly to the modem. They're usually behind a CGNAT service where that public IP is shared among many modems/phones/etc. You need to set up a VPN between your edge site and the central site where Ignition is running to allow them to connect to each other.

My guess is that you'll need someone more versed in secure networking to handle this (don't attempt to just open firewall ports on the modem as it opens you up to hackers).

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