Tomato also offers a wireless bridge mode called ‘Ethernet Bridge.” In ‘Ethernet bridge’ mode, the router connects to the host router but it does not repeat the wireless signal. This is similar to client bridge mode. But the difference is that the router is on the same subnet. So instead of creating a subnetwork, it becomes part of the primary LAN.
Router Bridge, Connect Two Routers – Router Behind Router
When you create a bridge between two routers, you are actually connecting two separate LAN segments. So before you start connecting wires to the wrong ports, you have a couple of decisions to make. Why? Because “how” you connect those Ethernet cables is very important. Then set your IP address, subnet and DHCP range and you’re done!