R200 How to bridge LAN/WAN ports and still get Voip

Hi Guys

I am trying to figure out how to bridge the LAN and WAN ports so the voip can still work.

When I put the unit into bridge mode I cannot find where to put the DNS server address or Gateway of the rooftop radio.

Attached is a diagram of what I wish to do. 

Your assistance is much appreciated.

Please check this post , should be of help .

http://community.cambiumnetworks.com/t5/cnPilot-R-series-R201-R201P/How-to-bridge-LAN-and-Wireless-data-from-R200-201-to-external/m-p/57360#U57360

Thanks that looks to be most helpful