Auguste Kerckhoffs
Dr
Auguste Kerckhoffs (
19 January 1835 -
1903) was a
Dutch linguist and
cryptographer who was
professor of languages at the School of Higher Commercial Studies in
Paris in the late
19th century.
Kerckhoffs was born in
Nuth, the
Netherlands, and was baptised as
Jean-Guillaume-Hubert-Victor-François-Alexandre-Auguste Kerckhoffs von Nieuwenhof, although he later shortened his name. Kerckhoffs studied at the
University of Liège. After a period of teaching in schools in the
Netherlands and
France, he became a professor of German at the
Parisian
Ecole des Hautes Etudes Commerciales and
Ecole Arago.
He is best known today for a series of two essays he published in
1883 in
le Journal des Sciences Militaires ("Journal of Military Science") entitled
La Cryptographie Militaire ("Military
Cryptography"). These articles surveyed the then state-of-the-art in military cryptography, and made a plea for considerable improvements in French practice. They also included many pieces of practical advice and
rules of thumb, including six principles of practical cipher design:
# The system should be, if not theoretically unbreakable, unbreakable in practice.# The design of a system should not require secrecy and compromise of the system should not inconvenience the correspondents (
Kerckhoffs' principle).# The key should be rememberable without notes and should be easily changeable# The cryptograms should be transmittable by telegraph# The apparatus or documents should be portable and operable by a single person# The system should be easy, neither requiring knowledge of a long list of rules nor involving mental strain
The most well-known is the second of his six principles, also known as
Kerckhoffs' principle. It can also be understood as the idea that the security of a cryptosystem must depend only on the
key", and not on the secrecy of any other part of the system.
In
1885, Dr. Kerckhoffs became interested in the
constructed language Volapük, and for several years was a leading member of the Volapük movement, and Director of the Academy of Volapük. He published several books on the subject and introduced the movement to
France,
Spain and
Scandinavia through a series of public lectures.
*
La Cryptographie Militaire — French original and translations into English
