(
Secure
SHell) A security protocol for logging into a remote server. SSH provides an encrypted session for transferring files and executing server programs on all platforms. Also serving as a secure client/server connection for applications such as database access and email, SSH supports a variety of authentication methods. See
headless system.
SSH was developed in the mid-1990s by Helsinki University researcher Tatu Ylönen as a secure alternative to non-secure telnet, rlogin and rsh programs for Unix servers. SSH-2, a more advanced version introduced in 1998, was standardized by the IETF and is not compatible with SSH-1.
Secure File Transfer: SCP and SFTP
Secure Copy Protocol (SCP) is a version of the Unix remote copy (rcp) command that is widely supported on Unix systems running SSH-1. The SSH File Transfer Program (SFTP) was developed by the IETF for transferring files with SSH-2.
OpenSSH
An open source version of SSH is available from the OpenSSH group (www.openssh.org) as well as commercial vendors such as SSH Communications Security Corporation (www.ssh.com), the company founded by Ylönen. See
FTPS.