Which protocol is primarily used to remotely communicate with devices using a command-line interface?

Which protocol is primarily used to remotely communicate with devices using a command-line interface?

• A. Telnet
• B. SSH
• C. FTP
• D. HTTP

Answer: (A)

Remote management of devices via a command-line interface is the classic use case for Telnet. It establishes a TCP connection to the device and provides a text-based terminal session, so you can log in and issue CLI commands as if you were physically at the device. That direct, interactive CLI session is what the question describes. The other options serve different purposes: FTP is for moving files, HTTP is for web content, and SSH offers a secure, encrypted remote shell (a modern, secure alternative to Telnet). Telnet fits the described scenario because it is the protocol historically designed to provide remote CLI access.

Remote management of devices via a command-line interface is the classic use case for Telnet. It establishes a TCP connection to the device and provides a text-based terminal session, so you can log in and issue CLI commands as if you were physically at the device. That direct, interactive CLI session is what the question describes. The other options serve different purposes: FTP is for moving files, HTTP is for web content, and SSH offers a secure, encrypted remote shell (a modern, secure alternative to Telnet). Telnet fits the described scenario because it is the protocol historically designed to provide remote CLI access.