There are a couple of different ways to execute commands or run
programs on a remote machine and have the output, be it text or
graphics, sent to your workstation. The connections can be
secure or insecure. While it is of course advised to use secure
connections instead of transporting your password over the
network unencrypted, we will discuss some practical applications
of the older (unsafe) mechanisms, as they are still useful in a
modern networked environment, such as for troubleshooting or
running exotic programs. The rlogin and rsh commands for remote
login and remote execution of commands are inherited from UNIX.
While seldom used because they are blatantly insecure, they
still come with almost every Linux distribution for backward
compatibility with UNIX programs. Telnet, on the other hand, is
still commonly used, often by system and network administrators.
Telnet is one of the most powerful tools for remote access to
files and remote administration, allowing connections from
anywhere on the Internet.