These URL schemes are defined in RFC 1738, and are used for logging in via a terminal emulator. They have the form
but the password component is ignored. By default, the
telnet scheme is handled via Tramp (see Tramp).
To handle rlogin, telnet and tn3270 URLs, a
tn3270 (the program names and arguments are
hardcoded) session is run in a
Well-known ports are used if the URL does not specify a port.