Any feedback is very welcome.
I am human, and prone to making mistakes. If you find any, fixing them is of my highest interest. I will try to answer all e- mail, but I am busy, so don't get insulted if I don't. I am not a security expert, so don't bitch me if your machine has taken on fire after you have set up some firewalling rules. The protected network can't reach the internet, and the internet can not reach the protected network.