Wednesday, 17 February 2016

Breaking Historical Ciphers: An Emerging Team

Breaking historical ciphers in an interesting field; it combines two rather different disciplines, cryptanalysis and history. Where history has touched on cryptology in the past has been where codebreaking has had some historical importance, such as the Allies breaking of the German and Japanese codes and ciphers during World War II. Cryptological history is another historical discipline that unfortunately lives largely in the shadows of historical research. Most historians probably know little about it and for some it probably does not exist.

Programs for breaking historical ciphertexts is therefore a unique chance for those of us who are interested in the cryptanalysis of classical and historical codes and ciphers and the history of cryptology. The field is very promising for many reasons. Firstly, for the cryptanalysts, both amateur and more seasoned actors, there is a chance to attack real systems used in the real world. The effort will give the cryptanalyst new and detailed insight into classical cipher systems and methods, which might reveal new information about their strengths and weaknesses. Furthermore, attacking hard cryptanalytical problems will also bring the reward of developing new and refined methods of solution. The final reward it to discover a previously unknown or undisclosed plaintext that might be of historical significance. Secondly, if the recovered plaintext is of historical or public interest then there will  be the added reward of media interests and especially academic interests among historians and other working in related fields. This media interest might open the eyes of people who firstly will discover the work done by the small community of historical cryptanalysts, but secondly and more importantly they may wish to take part in the work on breaking historical ciphers.

To prevent historical cryptanalysis to end up in the box marked “Dying or Extinct Species” there is an urgent need for help outside the cryptological field. We need historians and others, such as the many ‘archive rats,’ to tell us about interesting code- and ciphertexts that we can attack. To further this symbiosis there is a need for all of us to make an effort to inform at all levels about this interesting work. Therefore I ask you to please go out and become a missionary for historical codebreaking. Stand on the roof tops and shout: “We need historical ciphertexts. Now!”

Last year there was an attempt that originated largely in the academic fields of philology and history to get funding from the European Union for a program for historical cryptanalysis. An application for funding from COST, European Cooperation in Science and Technology, was made for a project called HICRYPT,   “Historical Cryptology – Unlocking Europe’s Encrypted Heritage.” Unfortunately the project did not get funding last year, but perhaps there will be other opportunities. The world’s economic situation is of course not favourable at the moment for projects that have rather weak foundations both in the academic world and elsewhere. It is therefore very important that when you get significant results from your historical codebreaking you inform the public and other interested players.

HICRYPT had as aim to decipher rather old encrypted historical texts such as the 250-year old text deciphered by Christiane Schaefer, Wolfgang Hock and Kevin Knight and described in Wired Magazine in November 2012, “They Cracked this 250-Year-Old Code and Found a Secret Society Inside.” This story made headlines around the world and it is the kind of break that makes waves well outside the academic communities and the small world of historical codebreakers.

Now you might say, didn’t he get his title wrong. Should it not be an “An Emerging Field” instead of “An Emerging Team.” Well, hopefully it will develop into an emerging field but my intention is to pay tribute to a small team of people who during the last few years have made significant progress in breaking historical cipher systems. They are George Lasry, Nils Kopal and professor Arno Wacker. Professor Wacker is the head of the research group “Applied Information Security” at the University of Kassel, where Nils Kopal is a Ph.D student and where also George Lasry now works on his Ph.D.

The team has already published three excellent articles in the journal Cryptologia, “Solving the Double Transposition Challenge with a Divide-and-Conquer Approach,” “Automated Known-Plaintext Cryptanalysis of Short Hagelin M-209 Messages,” “Ciphertext-only cryptanalysis of Hagelin M-209 pins and lugs,” and other publications are being prepared. However, before you dive in to study these interesting articles I would advice you to set aside one hour and listen to a talk George Lasry presented to the students and staff at the University of Kassel in October 2015, “Cracking Unsolved Historical Ciphers.” His talk is worth listening to and you probably will, like me, be inspired by his enthusiasm and great love for cryptology  and cryptanalysis. The rush of adrenaline you experience when you break one of these ciphers and see the plaintext starting to emerge is, as he describes it, a unique experience.

Having payed tribute to this outstanding team I should nevertheless add that there are others out there who are just as dedicated and who also have my great admiration. Some of them like to keep out of the limelight but that does not mean that they are lesser cryptanalysts, a few of them are simply amazing. I am honoured to count them among my friends. And I must not forget Klaus Schmeh for his tireless work of discovering new crypto challenges and new historical texts with cryptographic puzzles. If there is one person who keeps us supplied with cryptograms it is Klaus Schmeh.

And I should like to thanks my friend Christos who made me discover the talk of George Lasry, “Presentation on Solution of Historical Ciphers.” Thank you Chris.

No comments: