Why is it said that FTP sends control information “out-of-band”?
It is said that FTP sends control information “out-of-band” because FTP uses two different parallel connections to transfer a file.
It uses a control connection and a data connection in parallel. Control connection is used to send information such as user identification, password, commands to ‘put’ and ‘get’ files. Data connection is used to send the file. Because of this control connection(separate) FTP is “out-of-band”