Another method of salt production used by Morton Salt is the evaporation of salt brine by steam heat in large commercial evaporators, called vacuum pans. This method yields a very high purity salt, fine in texture, and principally used in those applications requiring the highest quality salt.
And finally applications use TCP or UDP connections to exchange the data that makes up the application protocol: logging in to servers, requesting and transmitting Web pages, delivering e-mail, and so on.
Simple File Transfer Protocol (the first protocol abbreviated SFTP), as defined by RFC 913, was proposed as an (unsecured) file transfer protocol with a level of complexity intermediate between TFTP and FTP. It was never widely accepted on the Internet, and is now assigned Historic status by the IETF.