Today public Wi-Fi networks are widely used, but that does not mean that we do not have to take extreme precautions. In that sense, we must never forget about our security, and we must always have a VPN connection. Sometimes, there are times of the year such as summer vacations, Easter, or long weekends when having a service of this type is very necessary. For our greater peace of mind we should opt for a paid VPN, because the free ones sometimes end up selling part of our data. The other safe and free alternative is to create a VPN server at home, in this tutorial we are going to talk about which ports to open for a VPN if you use the PPTP, L2TP, OpenVPN, IPsec and WireGuard protocols.