A friend of mine (actually, a co-worker) want to play a little game with me: we both want to set up a web server at home and try to hack each other. Since we are both web app developers, we think it would be a good exercise for us to learn both the defense and the attack of such servers.
We will install a VPN so we can do our stuff without alerting/disturbing anyone else. However, we plan to secure our servers as much as we can so having them face the internet (instead of using a VPN) wouldn't be a big worry for us.
Finally, we will give each other written permissions before we start doing anything.
My question is: If we wouldn't use a VPN and our server would be serving web pages on the internet, could our scans, brute force attacks, etc disturb other people?
Here I think more of our respective ISP (and possibly others?). What could we do to mitigate the risk of getting into troubles instead of using the VPN? Maybe it doesn't make any difference?
I want to add that I will use a VPN regardless of the answers and we both have no malicious intention whatsoever. We want to compete, that's all!!