Your best friend for file transfer.Fetch
Fetch supports a variety of different types of connections to servers: FTP (no security), SFTP, FTP with TLS/SSL (FTPS), FTP with GSSAPI (Kerberos), and FTP with KClient (Kerberos). Not all servers support all these choices; be sure the server you're connecting to supports your choice, or you will receive an error.
You can specify the connection type with the Connect Using pop-up menu in the New Connection dialog and New Shortcut dialog. The security of a connection is indicated by a padlock icon just above the file list in transfer windows and in shortcut list windows.
The most common type of connection. A plain FTP connection, with no extra security beyond possibly asking for a password — your data and password are not protected or encrypted in any way. (Some servers use One-time Password or S/Key to protect the password.)
SFTP stands for "SSH File Transfer Protocol." When you connect to a server using SFTP, it uses SSH encryption to protect the connection between your Macintosh and the server. This protects your password and your data, preventing an eavesdropper from watching and learning them as they travel over the network. See the SFTP help topic for more information.
FTP with TLS/SSL
Also known as FTPS. When you connect to a server using FTP with TLS/SSL, it uses TLS (Transport Layer Security) or SSH (Secure Sockets Layer) encryption to protect the connection between your Macintosh and the server. This protects your password and optionally your data, preventing an eavesdropper from watching and learning them as they travel over the network. Normally Fetch uses the AUTH TLS (also known as FTPES or Explicit SSL) method of establishing FTP with TLS/SSL connections; to use SSL connect (also known as Implicit SSL) select this option and enter 990 in the Port field. See the FTP with TLS/SSL help topic for more information.
FTP with GSSAPI
Connect to the server via FTP, using Kerberos for authentication. GSSAPI is an interface to Kerberos, a network security system. When you choose this option, you can securely connect to a server using your Kerberos tickets instead of a password. Optionally you can also encrypt your data using Kerberos. Generally you shouldn't choose this option unless you know you're using other Kerberos services as well. See the Kerberos help topic for more information.