In FTP, there are three types of Transmission modes stream, block, and compressed.
There are two different transfer mode in FTP, ASCII and binary mode. By default, TurboFTP uses the Auto mode, whereby any file that matches one of the types (file extensions) specified in [Options. Advanced. Text file mask] will be transferred in ASCII mode, otherwise it will be transferred in binary mode.
Transmission mode refers to the mechanism of transferring of data between two devices connected over a network. It is also called Communication Mode. These modes direct the direction of flow of information. There are three types of transmission modes.
FTP may run in active or passive mode, which determines how the data connection is established. In both cases, the client creates a TCP control connection from a random, usually an unprivileged, port N to the FTP server command port 21.
Simplex communication is a communication channel that sends information in one direction only. The International Telecommunication Union definition is a communications channel that operates in one direction at a time, but that may be reversible; this is termed half duplex in other contexts.