Secure Shell (SSH)

Secure Shell (SSH) is a cryptographic protocol and interface for executing network services, shell services and secure network communication with a remote computer. Secure Shell enables two remotely connected users to perform network communication and other services on top of an unsecured network. It was initially a Unix-based command but is now supported on Windows-based systems as well.

SSH was primarily designed to enable a user to securely log on to a remote computer and perform shell and network services. For example, it could be used by network administrators logging into a remote Web server. It is also considered a secure replacement to the Telnet, RSH and Rexec protocols. Typically, SSH-based communications/processes work on a client/server architecture consisting of a client and server SSH. The client is securely authenticated and connected, and sends encrypted commands to be executed on the server. Both the client and server are authenticated using RSA public key cryptography based digital certificates. SSH uses AES, IDEA and Blowfish as the encryption algorithms.