Prior to starting DNSFilter, I spent most of my career in Information Security, working for companies like ITA Software (acquired by Google) and Veracode, finding ways to get around normal system behaviors. As a result, I have a lot of experience in my DNA in getting around and through networks.
I’m going to step through various methods of getting around network restrictions, whether content filters, firewalls, captive portal, etc. I’ll explain the method, why it works, and what to do to prevent it.
Tunnel your traffic via VPN
This is probably the first method users think about using. It’s simple and effective; when it works. Negatives are that it adds latency to your traffic, as you’re going through the intermediary network, and the farther away it is from where you are, the slower your Internet usage will be.
Typical ports to firewall:
Basic prevention would be to block VPN ports which are not being used for other purposes (You can’t block 80 or 443 in this easy manner).