I want to ensure that when the VPN connection on my computer drops, no app or service on my system should be allowed to access the internet. Basically what I am trying to do here is to ensure that any apps on my system should be able to access the internet only through the VPN and just get timed-out if the VPN connection does get dropped for any reason.
I specifically want to achieve this only through the use of firewall rules on the Windows Firewall without the use of any third party apps.
I read somewhere a long time ago that there is a technique called "black-holing" , to achieve this, but I could not find any detailed info on the internet that explains how to achieve this by setting rules in the Windows Firewall.
I have been trying to configure my system according to the suggestions given by @Appleoddity and Binarus but with no success so far.
I have edited my question to make it more clearer.
As long as no third-party kill-switch/VPN Client/Software needs to be installed, I am fine.
I want to know as to how to ensure that a particular app (a bit-torrent client for example) can be prevented from accessing the internet at all if the VPN connection drops for any reason whatsoever.
Here I want to mention that the VPN Client that I am using is the native Windows 7 VPN Client and that the IP address of the VPN Server that I would be connecting to (through L2TP, SSTP or even PPTP) will always be the unchanged. I am on a wired LAN connection that's connected to the router (No need to dial-up).
When I am connected to the VPN, the server would always be 22.214.171.124 (For example). In other words, the IP will not change each time I connect to the VPN but stays static. That would make things a lot easier for us to configure, I believe.
I do not want to use the VPN Client offered by my VPN provider and so once again, this should make twhat I am asking more specific.
I am asking for a very specific answer describing what exactly needs to be done to ensure that the internet access to the system immediately gets killed, the moment the VPN drops, without exposing my real IP to the outside.
I am OK if the connection times out, as long as my IP is not leaked out.
In other words, I am looking for the configurations for an internet "kill-switch" that would ensure 100% that my apps would not access the internet using my real IP, should my VPN connection drop.
Thank you for the answers so far.