1.Internet Protocol Security (IPSec): Internet Protocol Security, known as IPSec, is used to secure Internet communications over IP networks. IPSec secures Internet Protocol communications by verifying the session and encrypting each data packet during the connection. IPSec runs in 2 modes:
  Shipping method
  Tunnel mode
2.Layer 2 Tunneling Protocol (L2TP): L2TP or Layer 2 Tunneling Protocol is a tunneling protocol that is often combined with another VPN security protocol such as IPSec to establish a highly secure VPN connection . L2TP creates a tunnel between two L2TP connection points, and the IPSec protocol encrypts data and maintains secure communication between the tunnel.
3.Point-to-Point Tunneling Protocol (PPTP): PPTP or Point-to-Point Tunneling Protocol creates a tunnel and limits data packets. Point-to-point protocol (PPP) is used to encrypt data between connections. PPTP is one of the most widely used VPN protocols and has been in use since the inception of Windows. PPTP is also used on Mac and Linux in addition to Windows.
4.SSL and TLS: SSL (Secure Sockets Layer) and TLS (Transport Layer Security) create a VPN connection where the web browser acts as the client and gives the user access to specific applications instead of the entire network being banned. Online shopping websites often use SSL and TLS protocols. It's easy to switch to SSL using a web browser and requires virtually no user action because web browsers have SSL and TLS built in. SSL connections have “https” at the beginning of the URL instead of “http”.
5.Secure Shell (SSH): Secure Shell or SSH creates a VPN tunnel through which data transfer takes place and also ensures that the tunnel is encrypted. The SSH connection is created by the SSH client and data is transferred from the local port to the remote server through an encrypted tunnel.
6.SSTP (Secure Socket Tunneling Protocol): VPN protocol developed by Microsoft that uses SSL to secure the connection but is only available for Windows.
7.IKEv2 (Internet Key Exchange version 2): VPN protocol that provides fast and secure connections but is not widely supported by VPN providers.
8.OpenVPN: Highly secure and configurable open source VPN protocol, widely supported by VPN providers and considered one of the most secure VPN protocols.
9.WireGuard: A relatively new and lightweight VPN protocol that aims to be faster, simpler, and more secure than existing VPN protocols.