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The art of cryptography: cryptanalytic world records

This course is listed in Aachen Campus as The art of cryptography: Cryptanalytic world records and in Bonn Basis as The art of cryptography: Cryptanalytic world records.


Prof. Dr. Joachim von zur Gathen


Daniel Loebenberger and Konstantin Ziegler

Time & Place

First meeting: Monday, 07 April 2014.


The exam dates have been fixed.

Exam: 24 July 2014, 13:00h - 16:00h, b-it, Rheinsaal

2nd Exam: 15 September 2014, 14:00h - 17:00h, b-it, b-itmax


This lecture's mailing list can be reached under

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Cryptanalysis is the art of breaking cryptographic systems. To attack for example the cryptosystem RSA, it is sufficient (though not necessary) to factor the underlying RSA modulus. Other algorithms, like ElGamal encryption or the DSA, can be broken by computing discrete logarithms in certain domains.  

Many attacks on symmetric cryptosystems are based on differential or linear cryptanalysis. These techniques are applicable to block-ciphers as well as hash functions. We study them on a small-scale version of AES and learn their powers and limits.

The lecture's aim is to give a thorough understanding of the techniques that were used to actually set real-world cryptanalytic world records by providing the necessary background.

About handins, credits and boni

To be admitted to the exam you need to earn at least 50% of the credits. Experience shows that you should try all exercises and tutorials. Students are encouraged to discuss the given exercises among each other. Still, every student has to write up his/her solutions on his/her own. Your solution has to be self-explanatory. Stating the final result is never enough.
  1. Always hand in to .
  2. Your solution must consists of
    • either: a single attached, printable file, best a PDF,
    • or: as text only in the mail body.

    A printout of this single thing must contain your name. Your solution can only be graded if the name is on the printout readable.

    Please make sure that also the printout is readable!

  3. Only in the case code has to be written, an additional tar/zip file is allowed for handin that contains your code ONLY.
  4. Try to keep the size of your mail fairly below 5MB.
  5. Obvious: credits are awarded for solutions that arrive within the respective deadline. Any post-deadline submission may be ignored.



Additional files




4+2 SWS.

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