PUBLIC MARKS with tags protocol & security

SFTP is mostly operated as subsystem of SSH-2. SFTP is a newer and more modern protocol, designed to perform in a manner similar to FTP. It is widely supported, even on non-Unix-like platforms, but not nearly as universally as SCP. Do not confuse SFTP (based on SSH) with FTPS/Secure FTP (based on SSL); they are distinct protocols which do not interoperate.