Connect Siemens PLC from a bridge network to internal network

We have a S7-1500 PLC and its currently connected to an IXON portal, PLC IP address is at while our Ignition network is at The supplier said we can use the IP address from the IXON portal and use a specific port address as it is forwarded directly to the PLC.

Now, I can simply create an OPC device connection if the PLC address is only aligned with our internal network but since its not, how can I do the suggestion of the supplier to use the IP address from the IXON portal which is very different from our internal Ignition network

When you say IXON portal, you have to manually go to the portal web page and click connect ?

If you have the IXON vpn software downloaded to the gateway PC and you have logged into the portal from the gateway machine and connected to the PLC, you can then just enter the PLC address in ignition as if it was a local PLC,

I use the same system albeit branded differently. To me this type of system is more of a on demand connection rather then a permanent connected VPN. You will also have monthly usage limits ? I use it for remote trouble shooting when needed.