File Transfer Protocol (FTP)
Separate control and data connections are used by the FTP between the client and the server. The FTP users can authorize themselves in the form of a username and a password. They can connect using anonymous names if the server isn’t configured to allow them.
For transmission security, the username and password need to be encrypted using the FTP and SSL.
FTP sessions work in passive or active modes. In active mode, after a client initiates a session via a command channel request, the server initiates a data connection back to the client and begins transferring data. In passive mode, the server uses the command channel to send the client the information it needs to open a data channel, because passive mode has the client initiating all connections, it works well across firewalls and network address translation (NAT) gateways.
