This is a very useful feature of any router. Why was this removed?
Most likely due to security issues with dmz.
I just read that DMZ and guest access will be enabled after the new update. No exact date on it, but it is coming.
It's probably there in capability, but the router's web GUI does not include it. This is the case on the Rev I router where you can change UPnP settings but only if you know the web page address to get to it because the menu system does not include it as an option.
Start a new topic or ask questions in the open forum.
