Block internet access to all programs except for whitelisted ones [duplicate]

Possible Duplicate:
Create firewall “profiles” for Windows 7

Sometimes my home internet connection drops, and I have to switch to a tethered mobile one which has a data limit. This means I have to close pretty much all applications except a fresh internet browser to make sure there are no bandwidth-wasting applications running.

I would like to know if there is a program that lets me block all programs' internet access by default, and use a whitelist to let applications through this block. On/Off switch would be nice, but closing the program and then re-opening it when I need it again is fine too.

Solution 1:

It's all about the firewall. Software-based or hardware-based.

Here is a good tutorial on how to make rules in windows 7

There are some 3rd party firewalls applications that can be easier to use like Comodo or ZoneAlarm (free versions), and then some not so free. But we need to know what OS you are running...