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Verizon FiOS FAQ »
Can I use my wireless or an extra router along with the Verizon provided router?where your Netgear is primary and your Actiontec is secondary. Essentially it sets up your Actiontec to connect to Netgear LAN-to-LAN. If you are already using all 4 LAN ports on Actiontec, you're stuck because anything going through the WAN port is being NATed, even if the firewall is set to minimum or none.
When you're reading that FAQ, it might get confusing. It was written for the Actiontec as primary, Netgear as secondary scenario. Same principles apply. You can use it for your circumstance.