SLAC National Accelerator Laboratory

Phasing Out Authenticated FTP

SLAC Computing
Updated: 11 Aug 2005

Authenticated (as opposed to anonymous) FTP generally sends a clear-text account name and password across the network making it one of the least secure protocols still in use today. We need to phase out the use of authenticated FTP as soon as we can. Anonymous FTP does not by its nature expose passwords, and is not a target of this phase out.

The first phases of this process occurred a number of years ago when we restricted FTP connections from offsite to a small set of approved FTP servers (those with hostnames beginning with "ftp"), and set the default configuration for newly installed Linux systems to disable FTP service. Historically, most Solaris systems have been configured with FTP service enabled. Early on Wednesday morning, 24 Aug 2005, we will bring Solaris desktops and servers into alignment by disabling FTP service except on the approved set of FTP servers.

Please note that we are only disabling the ftpd daemon; FTP client programs will continue to be available on all systems. If for some reason you must use authenticated FTP rather than a more secure alternative within the SLAC network, you will have to connect to one of our official FTP servers, such as FTP connections from SLAC to other sites will not be affected by this change; nevertheless the same concerns apply. We urge you to seek more secure alternatives when exchanging files with other sites and, most especially, to never use your SLAC password at another site.

In future steps, we need to eliminate authenticated FTP entirely. Secure alternatives include scp, sftp, rsync via ssh, bbcp, bbftp, and direct copy using the AFS client on Windows, Macs, or UNIX systems. UNIX users can find more information about most of these programs from their man pages. Windows users can find information about WinSCP, a popular scp client program for Windows, at

We would like to speak with you if you feel you cannot replace a current use of authenticated FTP with one of these protocols, so we can understand your requirements.

Please send any questions or comments about this upcoming change, or about the broader goal of phasing out authenticated FTP entirely, to

Len Moss
SCCS Systems Group

Len Moss