Can ProSoft Ethernet modules and gateways communicate with equipment on different subnets?
Yes, but as with any Ethernet equipment, the netmask and gateway settings used in our configuration must be correct for your network, and the routers and/or switches at the site must also be configured correctly.
Examples of switch and router configuration would include allowing broadcast traffic for ARP resolution and allowing traffic on ports required for application protocols, such as port 502 for Modbus RTU, port 20000 for DNP3, etc. If discovery services and remote configuration and diagnostics via Ethernet are required for in-chassis and gateway products, routers and switches must also permit UDP communication on ports 50000 and 3000.
Regarding the correct netmask and gateway settings for equipment on the network, ProSoft can provide general advice, but these are network architecture decisions which will often require assistance from those in charge of the network infrastructure and general IT for the site.
The following links provide great information on IPv4 addressing, and subnetting.