Thursday, September 18, 2014

Monday, September 15, 2014

Not quite true…

During WWII the top Allied officials in the US and the UK frequently communicated via a radio-telephone link protected by the Bell Labs A-3 speech scrambler. This device was not secure enough to be used at such a high level but since no other alternative was available it was used extensively by military personnel, diplomats and even Roosevelt and Churchill.

In order to secure these sensitive communications the Americans designed and built the Sigsaly device. The NSA website says about Sigsaly:
The SIGSALY system was inaugurated on 15 July 1943 in a conference between London and the Pentagon (the original plan had called for one of the terminals to be installed in the White House, but Roosevelt, aware of Churchill's penchant for calling at all hours of the night, had decided to have the Washington terminal moved to the Pentagon with extensions to the White House and the Navy Department building.) In London, the bulk of the SIGSALY equipment was stored in the basement of Selfridges Department Store, with an extension to Churchill's war room, approximately a mile away……….. With the coming of SIGSALY, the shortcomings of the less than effective A-3 were now a thing of the past’. 

This doesn’t appear to be the whole truth. While it is true that the system was installed in July 1943 it didn’t work properly till late 1943 and it only become fully operational in April 1944. Even after it was installed officials continued to use the A-3 for most of their communications since the only Sigsaly link was available at the Cabinet War Rooms and only a small number of officials had authorization to use it.
This information comes from the book ‘The woman who censored Churchill’, p112-3. I’ve added this information in Intercepted conversations - Bell Labs A-3 Speech scrambler and German codebreakers and German intelligence on operation Overlord.

Saturday, August 30, 2014

Upcoming essays

I think that I’ve covered practically all the important cryptologic cases of WWII in my current essays. In order to write more I’ll need access to files that the NSA is in the process of declassifying and that may take a while. However there are two stories that I’m going to cover in the future. One concerns the German research on the British Typex cipher machine and the other will be a summary of the work of the Agents section of the German Army’s signal intelligence agency.

Many authors claim that the German codebreakers had a look at the British Typex cipher machine and then gave up because they considered the task hopeless. Apparently that was not true for the German army’s codebrealers:


Referat 12
Referat 12 (Agents section) of the German Army’s signal intelligence agency OKH-Inspectorate 7/VI dealt with the codes and ciphers of enemy agents. During the war they solved the cryptosystems of British, French, Belgian, Polish, Czech, Russian, Greek, Bulgarian and Norwegian spies and saboteurs. A summary of their work during the period May 1942- February 44 (last available reports) is in order.