rcp A remote file transfer utility.
rexec A remote command-execution utility.
rlogin A remote login utility.
rsh A remote command-execution utility.
ruptime A utility that displays system information on uptime and the number of connected users.
rwho A utility that displays information on currently connected users.
Telnet A remote terminal utility.
trusted access A weak security system in which a system administrator designates remote hosts and users who are trusted to access the local system.