Niels Ferguson

Niels Ferguson ( born December 10, 1965 in Eindhoven ) is a Dutch cryptographer. He is currently working for Microsoft.

Ferguson has been involved in the Skein hash algorithm, the stream cipher Helix and the Wi-Fi WPA2 security standard. He also has 1999 along with Bruce Schneier and John Kelsey developed the random number generator Yarrow, which he later with Bruce Schneier further developed to Fortuna. On the CRYPTO 2007 conference he and Dan Shumow presented a document outlining a weakness in the specified by NIST controversial pseudo-random Dual EC DRBG.

Weaknesses of AES / Rijndael

Niels Ferguson has the Twofish encryption algorithm co-developed, which is inferior in competition for the Advanced Encryption Standard in the final. Ferguson presented a representation of the eventual winner, Rijndael algorithm as relatively simple continued fraction just before the decision. This he said in a presentation at the HAL 2001.


Ferguson claimed in the same lecture at the HAL to have broken the HDCP copy protection system. However, he could not publish his results because he would then have to worry due to the Digital Millennium Copyright Act, not being able to enter the United States. The master key of HDCP appeared nine years later on the Internet.

  • Niels Ferguson, Bruce Schneier: Practical Cryptography. Wiley, Indianapolis IN 2003, ISBN 0-471-22357-3 (English)