SSH means Secured Shell. Actually this is a protocol that is used to impart more security over the communication. This is a very flexible protocol. Many other applications can run over on the top of the layer, upon which SSH works and they don’t interfere on the other applications. SSH makes use of cryptography very well. You can also encrypt login session if SSH is used. With this facility, SSH makes impossible for the hackers to hack the encrypted password.

With the help of secure connection with SSH it is possible to transfer data or file from one computer to another computer. The authentication process is very rigid. Mainly it works in client server environment. A handshake happens between the client and the server for authentication process with the exchange of keys. The authentication process is like this:

· First the connection is done, then the client verifies if it was connected with the server previously.
· With the help of 128-bit encryption the client sends its identity to the server.
· The server approves it and the handshake is completed
· Now data can be transferred in both ways

As SSH uses 128-bit encryption, the data becomes very difficult for the hackers to decrypt.