FTPS (FTP Secure)

FTP extended with TLS encryption to secure both the control and data channels. Implicit FTPS (port 990) requires TLS from the very start of the connection, while explicit FTPS uses a STARTTLS-like AUTH TLS command on port 21 to upgrade the existing plaintext connection to TLS. FTPS is the standards-track approach to securing traditional FTP, distinct from the SSH-based SFTP protocol.