Honestly, I had an old router and just decided to replace it because so many other people had their ATA behind the router. I figured mine was just a crap router. I just took a chance, really.
The longer version of the story is that I had a Netgear running DD-WRT. Then, also, I had no problem with the ATA behind the router and had didn't have to port-forward to it or anything. But I'm constantly tinkering and bricked my Netgear, so I threw in an old Belkin I had laying around. But that's when I found I had to have my ATA in front of the router. After several failed attempts of trying to unbrick the Netgear, I gave up and bought the first router I could find that had port-forwarding in case I needed it. Lo and behold, the new Belkin worked flawlessly. So I decided to stop tinkering with the routers and just leave everything the way it is.
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