ssh stands for secure shell and it is used for providing encryption for network services like remote login or remote file transfers. It can also be used for wide range of other services like secure remote command execution, keys and password authentication, access control and port forwarding etc.
Why we recommend SSH (Key Features) :
Secure Remote Login :
Suppose you have login accounts on several computers on the Internet and you need to login from one computer to the other. Unfortunately, telnet and similar programs might transmit your username and password in plain text over the Internet, where a malicious third party can intercept them.Additionally, your entire telnet session is readable by a network snooper.
SSH completely avoids these problems. Rather than running the insecure telnet program, you run the SSH client program ssh.The client authenticates you to the remote computer’s SSH server using an encrypted connection, meaning that your username and password are encrypted before they leave the local machine.
Secure File Transfer :
Using traditional ftp protocol for transferring files over the network may cause the third party to inercept and read the packets as they travel over the network.
Using SSH, the file can be transferred securely between machines with a single secure copy command and the file is automatically encrypted as it leaves the source node and decrypted as it arrives on the destination.
Secure Remote Command Execution :
This might be very helpful for sysadmins to run commands and shell scripts on remote clients in order to manage configurations and troubleshooting.
Keys And Agents :
The more often you type a password, the more likely you’ll mistakenly type it in the wrong place. And on many systems, such mistakes are recorded in a system log file, revealing your password in plain text.
Using ssh, you only need to identify yourself for once and get secure access to all the remote clients by simply adding your public key to client’s authorized key.
Port Forwarding :
Suppose you are logged into a machine away from work and want to access a internal server at your office. That internal server is connected to the Internet,but a network firewall blocks incoming connections to most port. Using Ssh, you can establish a secure connection from specified TCP port on your local machine. Hence, a secure ssh tunnel is created to communicate with your internal server from outside the network.