Bridged AP is to extend your existing wired host router to have wireless capabilities. Clients connecting to OpenWRT will get an IP address from the wired host router.
OpenWrt bridges the LAN network with the WLAN of the device in Access Point mode. The advantage of bridging is that broadcast traffic from Wireless to LAN and vice versa works without further changes.
This document outlines the steps necessary to implement such a setup.
The changes below assume an OpenWrt default configuration, the relevant files are:
/etc/config/network and change the lan
interface section to set the IP your access point should have in the future:
This IP address must be an unused one within the network subnet of the main router. You could also change
dhcp and let the main router decide the access point's address, but of course from then on the access point needs a DHCP server and you will lose the ability to directly plug into your access point for maintenance.
/etc/config/wireless, locate the existing
wifi-iface section and change its network option to point to the newly created interface section.
Naturally, you should consider securing your wifi network.
Ensure the host router is connected with a lan port of the openwrt, not the wan port!
Enable the new wireless network.