SoftEther VPN Project develops and distributes SoftEther VPN. An Open-Source Free Cross-platform Multi-protocol VPN Program, as an academic project from University of Tsukuba, under the Apache License 2.0. SSL-VPN (HTTPS) and 6 major VPN protocols (OpenVPN, IPsec, L2TP, MS-SSTP, L2TPv3 and EtherIP) are all supported as VPN tunneling underlay protocols.
Point to Point Tunneling Protocol (PPTP) was created in 1999 and was the first widely available VPN protocol. It was first designed to tunnel dialup traffic! It uses some of the weakest encryption protocols of any VPN protocol on this list and has plenty of security vulnerabilities.
Layer 2 tunneling protocol (L2TP) doesn’t actually provide any encryption or authentication – it’s simply a VPN tunneling protocol that creates a connection between you and a VPN server. It relies on the other tools in the IPSec suite to encrypt your traffic and keep it private and secure. This protocol has a few convenient features, but certain issues prevent it from being a leading VPN protocol.
Secure Socket Tunneling Protocol (SSTP) is a fairly secure and capable VPN protocol created by Microsoft. It has its upsides and downsides, meaning that each user has to decide for themselves whether this protocol is worth using it. Despite being a primarily Microsoft product, SSTP is available on other systems besides Windows.
WireGuard is the newest and fastest tunneling protocol the entire VPN industry is talking about. It uses state-of-the-art cryptography that outshines the current leaders – OpenVPN and IPSec/IKEv2. However, it’s still considered experimental, so VPN providers need to look for new solutions to overcome WireGuard’s vulnerabilities.