A lot of times while using my Ubuntu 12.04, the internet connection fails and "the DSL connections" disappear from the internet menu. The only option available is VPN connection > Edit Connections.
To connect to my DSL connection again, I have to open up the Process Manager as root and stop the NetworkManager process. It then restarts and I get my dsl connection list back. But from a few days restarting the NetworkManager didn't help and my dsl connections list was still unavailable.
Also the frequency on internet connection failure is more on Ubuntu than on Windows 7.