KL-7

TSEC/KL-7 Simulator v1.0 Deze pagina in het Nederlands

This software is an accurate simulation of the KL-7 Cipher Machine. The KL-7, codenamed ADONIS or POLLUX, was an off-line rotor cipher machine, developed in the late 1940's by the American Armed Forces Security Agency (AFSA) and introduced by the newly formed National Security Agency (NSA) in 1952. The KL-7 served in the United States and several NATO countries until 1983.

The KL-7 simulator provides an authentic look and feel with its hands-on approach. The development of this simulator is based on publicly available information on the KL-7. It's principles of operation and most of the technical details are known. However, the internal wiring of the ciphering rotors and the stepping unit, which are considered part of the secret key settings, are still classified. The KL-7 simulator operates with the same cryptographic principles as the real KL-7 but consequently uses its own rotor and stepping wiring. Nonetheless, the KL-7 simulator provides authentic handling and operates just like the real KL-7. With all known surviving KL-7’s sanitized (stripped from rotor and stepping unit wiring), this simulator is the only remaining way to actually work with this beautiful machine and the simulator serves as an attempt to keep this machine and its history alive.

The program comes with a very complete 16 page manual (pdf), explaining the simulator, the technical details and the history of the machine.

Call for additional information! If you have have interesting information on the general (unclassified) history of the KL-7, I would love to receive that info to expand my KL-7 history section. You can contact me by e-mail or web post

Runs under Windows™ 98/ME/2000/XP/Vist, WINE on Linux or Parallels Desktop on MAC. All feedback, suggestions or comments are most welcome by sending an e-mail.

Download the simulator

Download the TSEC/KL-7 Simulator v1.0.4 (full install including runtime files) Zip 1670 KB
Download the TSEC/KL-7 Simulator v1.0.4 (exe file only) Zip 240 Kb (only when the required run-time files are already on your PC!)
Please check the readme file before installation.

Updates of the Manual

New manual update 0007-10/2009 now includes message examples on enciphering procedures and more drawings. This update is inlcuded in the latest simulator download. Those who already installed the KL-7 simulator, they can simply download the new manual by right-clicking the update link, select "Save Target As..." and save the pdf file as "KL-7 Help.pdf" in the installation folder (by default "C:/Program Files/KL-7" in case of a full install).

Alternative download site:
http://www.esnips.com/web/CipherMachines

For questions or problems:
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