PuTTY is a neat little program that allows you to do a lot of different things. The specific functions we will be using it for is the ability to tunnel SSH traffic through localhost (127.0.0.1:8080) to our VPS. In laymen’s terms, it will be transferring all of the data over Skype through a secure tunnel so that only the VPS you’re connected to is being exposed to anyone else.
This is a simple program that we will use that will transform the key we get from Amazon into something that PuTTY can use to automatically connect to our VPS.
Windows 7 Firewall
We’re using Windows 7′s Firewall (ANY Firewall can be substituted here) to disable Skype from connecting to the internet.
EC2 Amazon Access
Even though it requires a credit card to sign up for and activate, the only tier we’re interested in is 100% free. Amazon may authorize $1 to your CC just to verify that it’s real, but you won’t actually be billed any money. The free-tier that we will be using will be good for 1 year prior to activation.
The problem people have with Skype is that it tends to ignore whatever proxy you throw into the connection information for it. It doesn’t actually ignore the proxy, but it will simply add it to a list of nodes it will consider connecting to if you’re having trouble maintaining a p2p connection with whoever it is you’re chatting with. For security purposes, this makes it useless. Instead of adding our VPS to the Skype proxy list, we’ll add 127.0.0.1:8080. “What’s the point, though? You said it won’t even use that most of the time!” That’s where our Windows Firewall comes in! We’ll use Windows 7′s Firewall to block Skype from making ALL outbound connections to the internet. This means that when Skype tries to connect to the internet when you log in, it will see that there is no connection available. This forces it to look to any proxies the user has supplied for a connection. Ordinarily, these would also not work (since all outbound connections are blocked by our Firewall), however, localhost is not an outbound connection and therefore falls outside of W7′s restricted connections. This means we’ve effectively tricked W7′s firewall into becoming a routing tool! Skype will then begin tunneling traffic through localhost, assuming PuTTY is open and you are connected to your EC2 server that you set-up on Amazon.