Telnet is one of the tools we discussed earlier, but let's get a little deeper into it. Telnet is part of the TCP/IP protocol suite; it's a virtual terminal protocol that allows you to make connections to remote sites or other devices attached to a network that has Telnet configured, and it is of course password protected.
In networking, we usually use Telnet to go inside a router or switch to do show commands, re-configure some setting, or add a brand-new configuration, or to simply troubleshoot the device. It need not be said that you can Telnet from anywhere to anywhere if you have the privileges to do so. But let's look again at how, the configuration and telnetting into another device is done:
The preceding example is how you configure Telnet lines through the VTY terminal lines. You will always use a password, but in this example...