Which protocol is commonly used for establishing a secure connection over the internet?

The protocol commonly used for establishing a secure connection over the internet is Secure Shell (SSH). SSH provides a secure channel over an unsecured network in a client-server architecture, allowing for secure data communication. It is mainly used for remote login and command execution, making it an essential tool for managing systems and applications securely. The encryption that SSH employs protects against eavesdropping, connection hijacking, and other attacks, ensuring that the integrity and confidentiality of the connection are maintained.

Other protocols mentioned serve different purposes. File Transfer Protocol (FTP) and Telnet do not provide any encryption, making them insecure for communication over the internet. They can expose sensitive information to potential interception. Hypertext Transfer Protocol (HTTP) also operates without encryption, which can lead to data being transmitted in plaintext; however, its secure variant, HTTPS, does provide encryption, but it is important to note that in the context of this question, SSH is specifically recognized for establishing secure connections.