Now that we have covered the basics of VPNs and considered the pros and cons of each of the pfSense-supported protocols, it's time to cover configuration of a VPN connection, both under pfSense and on the client side. IPsec is the most difficult to configure on both sides, and you may not get it to work on your first try. OpenVPN is probably the easiest to configure, in part because it does not have as many options as IPsec.