I have seen people get confused between FTPS and SFTP and refer these technologies interchangeably. But the fact is they are not same.
FTPS (commonly referred to as FTP/SSL) is a name used to encompass a number of ways in which FTP software can perform secure file transfers. Each way involves the use of a SSL/TLS layer below the standard FTP protocol to encrypt the control and/or data channels. http://en.wikipedia.org/wiki/FTPS
Good news is IIS7 now supports FTPS - http://blogs.technet.com/extreme/archive/2007/05/23/ftps-in-iis7-is-sweeter.aspx
SSH File Transfer Protocol or SFTP is a network protocol that provides file transfer and manipulation functionality over any reliable data stream. It is typically used with the SSH-2 protocol (TCP port 22) to provide secure file transfer, but is intended to be usable with other protocols as well. - http://en.wikipedia.org/wiki/SSH_file_transfer_protocol