This is interesting: http://www.schneier.com/blog/archives/2007/05/scada_security.html About a year ago, Nessus released plugins for testing SCADA systems: http://blog.tenablesecurity.com/2006/12/nessus_3_scada_.html And SANS is always a good resource: http://www.sans.org/reading_room/whitepapers/warfare/1644.php Elazar