Constantly receiving this error on every server I join

This problem was fixed by disabling UPnP on my router's page.

I'm quite new to Battlefield 3 with only roughly around 11 hours playtime, and throughout that playtime I've encountered something really annoying. I don't know if this is a universal problem, or if I'm the only one, but almost every server I go to I'm interrupted by this error:

http://i.imgur.com/s4Bkd.png

My Internet connection is completely stable, and this error has come to the point where I can hardly join a server anymore. And once I do, I'll eventually disconnect from the game and receive this error.

Does anyone know if this is fixable, or what it means?

Thanks.