Which VPN security protocol is designed for tunneling over HTTPS?

The correct answer is SSL. SSL, or Secure Sockets Layer, is a protocol designed to provide a secure channel over a computer network. It operates by encrypting the data transferred between a client and a server, ensuring that any data sent over the connection remains confidential and intact. SSL is particularly well-suited for tunneling over HTTPS because it is the foundation of the HTTPS protocol, which is widely used to secure communication over the Internet by adding a layer of security to HTTP.

When data is transmitted through SSL, it creates a secure "tunnel" through which the data can flow safely, making it ideal for scenarios that require secure communication, such as online transactions or the transmission of sensitive information. This capability of SSL to create secure tunnels over HTTPS is what makes it the right choice for this type of VPN security protocol.

Other protocols listed serve different purposes or operate under different mechanisms and are not primarily designed for tunneling over HTTPS.