Stanford Linear Accelerator Center

Discontinuing Central Support for X-terminals

SLAC Computing
UNIX at SLAC
Updated: 11 Nov 2005

For many years SCCS has supported NCD X-terminals as low-cost, graphical interfaces to our public UNIX servers. However, these devices have dwindled in popularity at SLAC and the few remaining units are getting fairly old (note that NCD is no longer selling new X-terminals). Most importantly, however, NCD X-terminals are incapable of encrypting their network traffic and thus expose clear-text passwords -- not only your UNIX login password, but any other passwords you might happen to type during the course of an X-terminal session. Captured passwords are an increasing threat and SLAC's Security Team would like to eliminate all remaining systems that send clear text passwords as soon as possible.

Thus, sometime within the next year, but sooner if possible, SCCS will discontinue support for booting NCD X-terminals and for XDMCP login on the flora pool of public UNIX servers. (The latter change will also require some adjustment in how X-Windows software on Windows systems is used.)

We understand that people may need some time to acquire replacement desktop systems so we do not yet have a firm end-of-service date. We will be getting in touch with current X-terminal users to find out more about how (or whether) they are being used and to offer advice on a replacement or retirement plan. We will then announce a firm date for discontinuing X-terminal support.

Although this announcement only applies to SCCS-managed X-terminals, we recommend that other groups at SLAC that support these devices also consider phasing them out.

Len Moss
SCCS Systems Group


Len Moss