An Internet utility that lets one log on to remote computer systems is known as

Telnet (Teletype Network) is a network protocol used on the Internet or local area networks to provide a bidirectional interactive text-oriented communication facility. It allows a user to log on to a remote computer system and interact with it as if they were physically present at the terminal.

• Usenet is a collection of user-submitted notes or messages on various subjects that are posted to worldwide distributed newsgroups.
• File Transfer Protocol (FTP) is a standard network protocol used for the transfer of computer files from one host to another over a TCP-based network.
• Remote Net is not a standard technical term for a remote login utility.

While Telnet was the standard for remote access for many years, it has largely been replaced by SSH (Secure Shell) because Telnet lacks encryption and transmits data in plain text.