SSH-Secure Shell

SSH is a network protocol used to remotely access and manage a device. The key difference between Telnet and SSH is that SSH uses encryption, which means that all data transmitted over a network is secure from eavesdropping.

 

Like Telnet, a user accessing a remote device must have an SSH client installed. On a remote device, an SSH server must be installed and running. SSH uses TCP port 22 by default.

 

SSH relies on public key cryptography for its encryption.

 

Here is an example of creating an SSH session using Putty, a free SSH client:

 

 

NOTE – SSH is the most common way to remotely access a Cisco device