In the mid-'80s, a series of computer hacks spanning the globe were performed by members and associates of the Chaos Computer Club (CCC) in Germany. This was the first major international hacking event involving espionage, resulting in arrests, convictions, and the death of Karl Koch (a.k.a. Hagbard, as referred to in this story), a young first-generation hacker. The hacking events associated with the Chaos Computer Club persisted for over two years, involving hundreds of systems across the USA, Japan, and Europe. This resulted in a daily barrage of emails, meetings, and phone calls that consumed the majority of my time and that of my staff at the Fermi National Laboratory (Fermilab) in Batavia, Illinois.

"The Cuckoo's Egg" is a book written by Cliff Stoll that details his role in tracking and catching hacker Markus Hess and associates while Cliff was employed at the Lawrence Berkeley National Laboratory (LBL) in Berkeley, California. Cliff Stoll's book became a bestseller, and various media and publications documented his story, but his book did not include my efforts that have never been published and are significantly different from Cliff's. It primarily involves Karl Koch (a.k.a. "Hagbard"), Digital Equipment Corporation (DEC) computers (rather than Unix systems), and the creation of a network "trap" that directly resulted in identifying Karl Koch as my principal hacker, where he lived, and ultimately helped identify his associates with the German police. I wrote this story as a sort of addendum to Cliff Stoll's book to fill in the missing chapter and dubbed it "Cracking the Cuckoo's Egg" (i.e., "crack it" to discover what else was inside).