There are three main types of FTP connections:
– FTP: The default, unencrypted protocol using port 21 for control and port 20 for data transfer. It lacks security, as it sends usernames and passwords in clear text.
– FTPS (File Transfer Protocol Secure): An extension of FTP that adds security through Transport Layer Security (TLS) and Secure Sockets Layer (SSL) protocols, encrypting both control and data channels.
– FTPES (Explicit FTPS): Uses port 21 to establish a secure SSL connection upon user request, ensuring data security and allowing for the transmission of sensitive information.