FTPS
FTPS — FTP over TLS. See official source.
Definition
FTPS — extension of FTP standardised by RFC 4217 (October 2005) that adds TLS to encrypt the command and/or data connection. Not to be confused with SFTP (SSH File Transfer Protocol).
Origin
RFC 4217, edited by P. Ford-Hutchinson, formalises explicit FTPS (AUTH TLS) and implicit FTPS (port 990) modes. FTPS inherits FTP's limitations (NAT, port ranges) but adds encryption.
Use
FTPS is still used in banking and automotive EDI where regulatory audit mandates TLS encryption without requiring SSH. It is often seen as the underlying transport for AS3.