You have this enormous network and no one knows what's out there.

In a summer course in 1989 in order to graduate from Purdue University he started the development of the COPS program for identifying security issues on Unix systems under Gene Spafford first releasing it after leaving Purdue in late 1989. However within a few years the use of SATAN and similar tools known as vulnerability scanners became standard practice of security and IT professionals and lost all controversy. Dan Farmer (born April 5 1962) is an American computer security researcher.

Dan Farmer (born April 5 1962) is an American computer security researcher. In 1995 Farmer and Wietse Venema created Security Administrator Tool for Analyzing Networks (SATAN) one of the earliest network based vulnerability scanners.