Friday, September 1, 2017


In The Japanese FUJI diplomatic cipher 1941-43 I’ve added the following:

1). In ‘Allied exploitation of the improved J series codes’:

When the new J-19 system was introduced the US codebreakers were already familiar with the basic characteristics of the cipher and Rowlett quickly made important discoveries regarding the underlying code. However solution of the daily key settings was a difficult problem, especially since more resources were put into the solution of the traffic sent on the PURPLE cipher machine.

2). In ‘Australian effort’:

Progress in 1941 was slow and up to February 1942 the only keys solved were those for messages whose content was known (for example messages reporting the departure of ships). However in 1942 things progressed rapidly.

In March ‘42 a member of the British Foreign Office from Singapore who possessed an excellent knowledge of Japanese joined the section. At the same time personnel of the unit developed elaborate cryptanalytic methods for recovering the daily settings and by May ‘42 the section was able to read virtually all FUJI traffic and ‘all bigrams, except those of very rare occurrence, and most tetragrams had been recovered’.

3). In ‘OKW/Chi effort’:

The OKW/Chi designation for FUJI was system J-13/J2B4BCüRuW (Japanese 2-letter and 4-letter code with stencil and transposition – Raster und Würfel). FUJI messages were first solved thanks to a repeat message sent from Paris to Tokyo. The first message and the repeat had the same plaintext (with small variations) and they had both been enciphered with the same key. This mistake facilitated their solution and the basic characteristics of the system were identified.

The solution of the daily transposition settings and the different stencils was taken over by personnel of the mathematical research department, specifically by the mathematician dr Werner Weber.

According to Part 3 of the report I-181 ‘Homework by Dr Werner Weber of OKW/Chi’, Weber started working on Japanese diplomatic messages in July ’41 and he identified the system as a transposed code. The underlying code for some of the messages was the previously solved LA code, thus they could be read. The rest of the messages had a new code.

Solution of the new system and recovery of the code proceeded slowly in 1941. In September ’41 Weber was allocated a small staff to help him with the Japanese traffic and by February ’42 some material could be read. During the year the new system was solved and most of the circular and European/Middle East traffic could be read. In the period summer ’42 to summer ’43 the previous year’s indicators were reused and the old transposition keys and stencils were either repeated or were modified in a predictable manner (with some exceptions).

Tuesday, August 29, 2017

Info on Greek Army codes

A Greek file dated 1938 (1) mentions the following Army cryptosystems: small unit code 1937, large unit code 1937, small unit code 1938, mobilization code 1937, cryptographic lexicon 1935. 

Monday, August 21, 2017

Missing page from TICOM I-137

The TICOM report I-137 ‘Final report written by Wachtmeister Otto Buggisch of OKH/Chi and OKW/Chi’ that I recently uploaded was missing page 2.

Thankfully the NSA FOIA office has sent me the page, thus I have re-uploaded the file.

Missing page:

Tuesday, August 15, 2017

Book review – ‘TICOM: The Hunt for Hitler’s Codebreakers’

Signals intelligence and codebreaking played an important role in WWII. British and American codebreakers solved many important Axis crypto systems, such as the German Enigma machine and the Japanese Navy’s code JN25. These operations remained hidden from the public till the 1970’s, when several books finally acknowledged the Allied codebreaking successes.

Since then countless books have been written about the Allied codebreakers, their successes and their contribution to the overall war effort.

Information about the similar successes of the Axis codebreakers is much harder to find since the relevant material only started to be declassified in the 2000’s.

The material that has been declassified reveals that at the end of the war in Europe the US and UK authorities were interested in finding out as much as possible about the operations and successes of the German codebreaking organizations. For this reason the TICOM (Target Intelligence Committee) project was created. The goal was to send small teams into Germany in order to capture the German codebreakers and their archives.

A new book has been published that covers the operations and findings of the TICOM teams sent to Germany at the end of WWII. ‘TICOM: the Hunt for Hitler’s Codebreakers’ by Randy Rezabek is available in both paperback and e-book format.

The book starts in 1944, when the Anglo-Americans expecting the war to end soon had started planning for the capture of enemy sigint personnel and archives.  The joint US-UK effort was codenamed TICOM and six teams were formed to go into Germany and search for the German signal intelligence personnel and archives.

The operations of the individual TICOM teams are covered in the following chapters. Travelling through a war ravaged Germany they had to improvise and take risks in order to locate their targets. The teams managed to retrieve important enemy personnel and files, including the entire codebreaking unit of the German Foreign Ministry. Other great successes were the capture of a ‘Kurier’ burst-radio communications device in Northern Germany, multichannel radio-teletype demodulators found buried in a camp in Rosenheim and the retrieval of the OKW/Chi archive, found in metal boxes at the bottom of lake Schliersee in Bavaria.

The author not only describes the operations of the TICOM teams but also explains the organization, personalities and achievements of the German codebreakers.

The book contains maps and several rare photographs of personnel and material from that era. There is also an appendix with an overview of the different codes and ciphers used in WWII.

Q&A with Randy Rezabek

The author was kind enough to answer some of my questions.

1). How did you become interested in WWII cryptologic history and why did you decide to write a book about the TICOM operation?

Many years ago (35+) I was saving in the Navy and was stationed at a Naval Security Group intercept site running the local photo lab. I had a clearance and learned a bit through osmosis, but it wasn’t until I read Bamford’s book The Puzzle Palace that things became clear about what we were up to. I maintained an interest in things Sigint even though life moved on in different directions.
About 2010 I was diagnosed with MS and that created physical limitations on many of my activities, so I focused on TICOM as a pastime that could focus on.
I first learned about TICOM through another Bamford book Body of Secrets, also the account in The Ultra Americans by Parrish. I found the whole topic fascinating but little researched in the literature. Since then I have acquired a personal library of 150 or so volumes on Signit, intelligence and military communications.
Since nobody else had written a book on TICOM I thought that was a worthwhile goal.

2). How hard was it to find information about the TICOM teams and the information they gathered?

About the time I got serious about this I started doing follow ups with NSA and NARA. It was around this time that TICOM documentation started being released. It was a very slow process, especially with the NSA FOIA requests, they often took years, and by the time they replied the requested documentation had been released to NARA anyway. The release of “European Axis Signal Intelligence…” was a great boon to researchers. In addition to the overview, I compiled a list of 150 or so TICOM reports that were cited in the footnotes, this gave me a guide on what to look for. I also hooked up with some other researchers in the field, such as Ralph Erskine, Frode Weierud and you. I made the acquaintance with David Kahn, who was a great inspiration, and met and corresponded with Stephen Budiansky, all have helped me find sources and sharpened my knowledge.
Otherwise it was a matter of patience watching the slow drip, drip of releases over the years. NARA was a great help, when I started out there was no use of the Term TICOM in the descriptors. But by 2012 they had reorganize lot of the catalog and put the newer TICOM stuff into their own entries.

3). You said in the book that the reasons why TICOM remained classified into the 21st century is perhaps its greatest secret. Do you think it was simple bureaucratic inertia or something else?

At this point I think it was inertia. After the end of the cold war there was no real need to keep it secret from a security viewpoint. Human sources were long retired or dead, technologies and techniques were long superseded, and the use of captured German intelligence information against the Soviets would be obvious to even the most clueless observer.. But the law says a secret is a secret until properly declassified, even if everyone knows about it. And declassification is a laborious process with little priority: as I say in the book “nobody in the NSA ever got fired for not revealing a secret.”

4). Are you going to write more books on the subject?

At this point I think I have pretty well exhausted the topic. I tried to include as many details as possible in it to provide a guide to future researchers. If something comes out in future released that alter the story then I may do a follow up article or two. However, publishers don’t see enough profit in the story to bother, that why I had to publish it myself.

More TICOM reports

The NSA FOIA office has released the following TICOM reports: