Thank you for asking this question in the support community. Yes, you can absolutely enable the other Ethernet port. One of the main applications for the NV3430 is a T1 module with two Ethernet ports. It depends how they want to use the other Ethernet port as to how you would configure it; however, the concept is the same. You will need to enable the Ethernet port, provide it an IP address (not in the same subnet as the other port), and configure any firewall settings they may need.
If you would like to provide some additional details as to how they intend to use the port, I will be happy to provide any assistance I can.
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