Telnet and SSH are both protocols for remote access to a device over a network.

Telnet –

is a network protocol used for remote access to a device’s command-line interface (CLI).

It allows a user to log into a remote device and run commands.

Telnet is an unencrypted protocol, which means that data transmitted over the network can be intercepted and read by unauthorized parties.

SSH (Secure Shell) –

is a network protocol for secure data communication, remote command-line login, and other secure network services between two networked computers.

SSH provides encryption for data transmitted over the network, ensuring that the data cannot be intercepted and read by unauthorized parties. Additionally, SSH provides authentication mechanisms to verify the identity of the remote device and the user before granting access to the remote device.

To enable Telnet on a Cisco router, follow these steps:

Configure a password for the VTY lines:

Router(config)# line vty 0 4

Router(config-line)# password yourpassword

Router(config-line)# login

To enable SSH on a Cisco router, follow these steps:

Generate an RSA key pair:

Router(config)
# crypto key generate rsa