众所周知，OpenVPN（http://www.openvpn.net） 是比较著名的开源 VPN 软件，应该也有很多人使用过，虽然使用起来并不是很困难 ...

Every Linux user who takes their privacy seriously understands the importance of using a virtual private network or VPN. Establishing a secure connection to a VPN server protects a device’s IP address ...