AT&T U-verse 5031NV/Bridging

Bridging
There is no true bridge mode on the 2Wire routers. However, you can still configure
 * it such that almost all functions of your own router will work properly.


 * 1) Set your router's WAN interface to get an IP address via DHCP. This is required at first so that the modem recognizes your router.
 * 2) Go to Settings -> Firewall -> Advanced Configuration
 * 3) Uncheck the following: Stealth Mode, Block Ping, Strict UDP Session Control.
 * 4) Check everything under Outbound Protocol Control except NetBIOS.
 * 5) Uncheck NetBIOS under Inbound Protocol Control.
 * 6) Uncheck all the Attack Detection checkboxes (7 of them).
 * 7) Click Save.
 * 8) Plug your router's WAN interface to one of the 2Wire's LAN interfaces.
 * 9) Restart your router, let it get an IP address via DHCP.
 * 10) Log into the 2Wire router's interface. Go to Settings -> Firewall -> Applications, Pinholes, and DMZ
 * 11) Select your router under section (1).
 * 12) Click the DMZPlus button under section (2).
 * 13) Click the Save button.
 * 14) DO NOT reboot the modem as the settings will go all wonky and you will have to start over
 * 15) Reboot your router or renew the DHCP address, the Routers IP address should be your public IP