1. PPTP (Point-to-Point Tunneling Protocol):

PPTP is one of the oldest VPN protocols and is widely used due to its ease of setup. It creates a tunnel and encapsulates data packets, but the encryption used in PPTP is considered weak compared to more modern protocols. Despite its limitations in security, PPTP is known for its fast speeds and compatibility with most devices and operating systems.

2. OpenVPN:

OpenVPN is an open-source VPN protocol that provides robust security and encryption. It uses SSL/TLS encryption protocols to ensure secure data transmission. OpenVPN is highly configurable and works well across a wide range of network environments, offering strong security measures and the ability to bypass firewalls. Its main downside is that it can be slightly slower than other protocols due to the high level of encryption.