As you are mentioning ssh, sftp and ftp ind the same context, you need to clarify what you want.
You have either sftp which is a subsystem of sshd like scp as well and such it is "ssh" based.
ftps instead is secure ftp, e.g. ftp with ssl/tls.
see e.g.
http://blogs.msdn.com/technical_outb...-and-sftp.aspx for the differences
For configuring pureftp with TLS see:
http://www.pureftpd.org/project/pure-ftpd/doc -> TLS encryption