Markus Hess

Markus Hess, a German citizen, is best known for his endeavours as a hacker in the late 1980s. Alongside fellow hackers Dirk Brzezinski and Peter Carl, Hess hacked into networks of military and industrial computers based in the United States, Europe and the East Asia, and sold the information to the Soviet KGB for US$54,000. The hacked material included "sensitive semiconductor, satellite, space, and aircraft technologies".

Hess's hacking activities were discovered in 1986 by Clifford Stoll, an astronomer turned systems administrator of the computer center of the Lawrence Berkeley Laboratory (LBL) in California. Stoll's first job duty was to track a 75 cent accounting error in the LBL system. Early in his investigation, Stoll discovered that the LBL computer system was compromised and that the hacker had obtained "root" or systems privileges. Such a security compromise was more important than the accounting error. Stoll eventually discovered how the hacker broke in and identified the hacker's activities on the system. LBL management considered attempting to seal off the system from this hacker, but Stoll and his colleagues convinced LBL's management that this would not be effective. Ultimately, they installed a honeypot to ensnare the hacker.

Hess's initial activities started at the University of Bremen in Germany through the German Datex-P network via satellite link or transatlantic cable to the Tymnet International Gateway. Tymnet was a "gateway" service that a user called into that routed him to any one of a number of computer systems that also used the service. Tymnet was one of a number of services available that provided local telephone numbers, where directly accessing the computer would have been a long distance call. Users normally used packet switching services like Tymnet for their lower costs. Once he accessed Tymnet, Hess branched out to the Jet Propulsion Laboratory in Pasadena, California and to the Tymnet Switching System. It was through this switching system that he accessed the LBL computers.

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