Figure 1.--

Soviets authors have addressed World War II in great detail, primarily the titanic struggle on the Eastern Front. As far as we know, in the vast Soviet literature, the subject of code breaking is not addressed. Hopefully our Russian readers can confirm this or tell us what has been published on the subject. A Russian correspondent has provided us a review of a Russian book on Soviet cryptology. We are attempting to translate it. It discusses Soviet cryptology in some detail. The Soviets would have been interested in the transmissions of several diggerent countries, but the primary focus would have been on the Germans, the only country that had an army that was a major threat. It should be noted that Enigma was not the only encryption systenm used by the Germans. And the Soviets cracked many of these systems. They made some progress with Enigma, but just how much progress is unclear.

Code Systems

The German Army used multiple encryption methods. Enigma was only one such system. It is a common misconception that Enigma was the only one encryption method. Enigma waa used for the more important messages, but it was only one of many such codes.

Captured Equipment and Code books

Code breaking

The GRU Deciphering Department managed to crack more than 75 German military and Abwehr ciphers, reading more than 50,000 German encrypted communications. The Soviets thanks to broken German codes USSR managed to uncover the exact units that were encircled at Stalingrad, their exact numbers and supply situation. During the German campaign in the East, German Army used multiple encryption methods, not limited by Enigma (it is a common misconception that Enigma was the only one encryption method). By 1942 Deciphering department of GRU (Army Intelligence) managed to crack more than 75 German military and Abwehr ciphers, reading more than 50.000 German encrypted communications. For example, thanks to broken German codes USSR managed to uncover the exact units that were encircled at Stalingrad, their exact numbers and supply situation. As for Enigma… By 1943 Soviet cryptologists have already developed a mathematical model for Enigma decoding and began to construct a deciphering mechanism similar to the British Bletchely BOMBE, but the work stalled due to lack of resources. In the end, USSR was able to decipher all intercepted Enigma communications prior to late 1943, after which Germans actually considered Enigma codes broken by the Red Army (mostly a precautionary measure because they had no information to confirm that old machines were not captured and old ciphers were not compromised, so they had to update the whole system), which made the new communications unbreakable again.

Differences with Anglo American

A Russian correspondent tells us that while the Soviers made coonsiderable progress in cracking Enigma, there was considerable differenced from the Anglo-American codebreaking effort at Bletchley Park and Arlkington Hall. There were several fidderences, but the orimry difference was the timliness of the decrypts. Our Russian corespondent tellos us, "So the answer is: yes, USSR could read most of German secure communications. (after all, if you decipher it after a year of work it is still counts as “breaking” even though the message is useless now). But the operative deciphering (that allowed to decipher the messages in short time and use them while they were still “fresh”) was mostly on occasional basis, depending on availability of particular codes and protocols that were routinely changes from time to time. [Zhiltsov] Here are the differences our Russian reader sees:

Different Enigma versions

"There are different version of Enigma. Army one, Naval one, [Luftwaffe one,] Abwehr one, which were upgraded from time to time. Allied efforts were mostly spent on deciphering Naval Enigma. Soviet methods were mostly dedicated on breaking Army Enigma. No 'one code break to uncover the whole German communication network', that’s a myth, even Brits had no such capability." [Zhiltsov] We think it is true that the Naval Enigma was a high priority, but it is our understanding that th Anglo-Amerucans cracked the Army and Luftwaffe Enigma. We re not sure about the Anbwegr Enigma. The Anglo-Americans also creacked the high level Lorenz code.

Army proticols

"Different Army branches used different secure communications protocols that were also upgraded and changed from time to time. As you may know, it is not the encryption security that matters, but the correct protocols. Most successes of British deciphering of Enigma were from exploiting breaches in Naval communication protocols (and their relative reluctance to change them). USSR had the occasional ability (after obtaining and/or breaking certain codes for certain version of Enigma utilised under particular protocol to read German communications in one Eastern Front theatre for a certain period of time (month-two, until Germans change the protocol and close the window) and that’s all. So yes, we can say that, for example, USSR could read all communications during Battle of Stalingrad, but at the same time couldn’t read the same communications by German forces near Leningrad." [Zhiltsov]

Timliness

"Operative deciphering is what matters. The biggest achievement of British in breaking the German codes was not in actually breaking it, but in doing so fast, so that information was still fresh and could be used in war planning. The whole system was built around the speed. USSR had the ability to decipher most of German communication using more or less the same methods but without insights into particular protocols and code combinations used at the time of encryption it could take several months to decode. What’s the point if you can read all Enigma messages… half a year after they were actually sent?" [Zhiltsov]

Kriegsmarine vulnerability

Kriegsmarine relied on long-range radio communications (obviously), which allowed Brits to intercepts lots of encrypted information, use this massive array of data to break the codes and seek vulnerabilities in protocol. Come on, the remote meteo stations even transmitted weather reports in an encrypted form from time to time (if you have the same report from nearby you basically have plaintext + ciphertext combination which makes the task of uncovering the code easier)! On the Eastern Front, most important communications were sent via land lines (by both sides). You can’t intercept them unless you tap the wires directly (which could have been done via Soviet special forces, we just don’t have much information. Nevertheless, even tapping allows much reduced array of data for deciphering). Most radio communications that could realistically be intercepted by Soviet ELINT (even forward-deployed close to the frontline) was on low levels, lower than Divisional, maybe Corps, maybe Army-Corps level. And the most valuable communications are obviously ones that come from the top authorities directly. So in general USSR could objectively intercept less ciphertexts than UK and this slowed down the decryption speeds, there were less 'cribs' found in ciphertexts (mistakes in protocol that allow easier deciphering). In fact, I’m sure the USSR did the best they could and UK in the same scenario simply couldn’t have deciphered more of communications as well." [Zhiltsov]

Sources

Zhiltsov, Konstantin. Moscow University. (January 3, 2019). oscow

Created: 7:45 AM 1/6/2019
Last updated: 7:45 AM 1/6/2019