Secure file transfer protocol

The term secure file transfer protocol can refer to both following protocols:

• SSH file transfer protocol, a file transfer protocol specifically developed by the IETF to run over secure shell (SSH) connections

• Secure FTP, the practice of running a normal FTP protocol session over SSH (FTP over SSH)

The ambiguity comes from the acronym for the SSH-based SSH File Transfer Protocol having the same acronym as one of the terms referring to tunneling true FTP connections over SSH: Secure FTP. The real SFTP protocol does not use FTP, but it is implemented in a diverse array of clients such as FileZilla, WinSCP, and the command line program 'sftp' from the OpenSSH project included on most GNU/Linux and BSD distributions. Clients which implement tunneling raw FTP over SSH (so-called Secure FTP) are much more rare, but include version 3 of SSH Communications Security's software suite, and the GPL licensed FONC.