School of
Information Technology and Electrical Engineering

One of the most challenging unsolved cryptograms of the Irish Republican Army  ̶  created in the 1920s  ̶  has been decoded for the first time by a University of Queensland data scientist.

The solution to the cipher has evaded cryptologists for years, but through perseverance and skill Dr Richard Bean managed to develop a program to crack the code.  

“I was very happy to see that one of the last uncracked IRA ciphers had been solved and that my program was able to accurately break the cipher,” Dr Bean said.

Dr Bean determined the 51-character code, a ‘columnar transposition cipher’, deciphered to – RE: Gelignite Scotland states they raided and obtained some of this.

“The cipher is from a book published in 2008 co-authored by Jim Gillogly, who was the first person to publicly solve the first three sections of the famous cipher sculpture, Kryptos,” he said.

“It had also been worked on by George Lasry, a Google employee who recently completed a PhD at the University of Kassel on classical cipher solutions.

“After seeing the calibre of the people who had previously attempted to decipher the code, I knew it was going to be difficult.

“I wanted to see if I could develop techniques that would help me see the answer. It really is an art as well as science.”

Dr Bean’s previous research in mathematics, including writing fast search algorithms, pattern recognition and statistics, helped in developing the code-cracking program.

Professor Neil Horrocks worked with Dr Bean at UQ’s Redback Technologies Research Centre and said his colleague often took a dogged approach to problems he was presented with.

“I have seen this a number of times in his work in our research centre and it’s a trait that makes him a valuable member of our team,” Professor Horrocks said.

“Who would have guessed he was even working on solving this problem?”

IRA Cipher: GTHOO RCSNM EOTDE TAEDI NRAHE EBFNS INSGD AILLA YTTSE AOITDE.

Solution: REGELIGNITSCOTLANDSTAESTHEYRAIDEANDOBTAINEDOMEOFTHLS

Media: School of Information Technology and Electrical Engineering, Dr Richard Bean, r.bean1@uq.edu.au, 0431 893 907; EAIT Communications, Paige Ashby, p.ashby@uq.edu.au, 0430 511 615