Recall Help...??? - Yamamoto/Yamaguchi Discussion Inland Sea (Truk?) 1942 (43?).

[Tangles2]

Greetings All

I've got a persisting brain itch I'd like to scratch but have had no luck addressing. I'm wondering if anyone out in forum land can give me a bit of help. Shortly before II was struck by a serious health issue in 2022 I think, I read a post in one of the threads in which Yamamoto held a meeting with Yamaguchi to discuss signals security and use of deception. ITTL Yamaguchi had survived Midway and was commander of the KB, training up in either Hokkaido or the Kuriles when he was called to confer with Yamamoto regarding its future employment. The thing was that the ideas in the post intrigued me, and the niggle has persisted despite my health issues, but it's taken me till now to catch up and try and pursue it further. The trouble is with cancer and radiation therapy I've lost track of the original post or thread that initiated this niggle, and now I can't find it. I'm wondering if anyone out there can recall a similar post or thread to point me too. I know it's a long shot but if anyone has some ideas or recalls the narrative described I'd appreciate it if you can direct me to possible posts. Thanks for any assistance I hope to hear from people regarding anything remotely like this. Tks T.

 

[Belisarius II]

Greetings All

I've got a persisting brain itch I'd like to scratch but have had no luck addressing. I'm wondering if anyone out in forum land can give me a bit of help. Shortly before II was struck by a serious health issue in 2022 I think, I read a post in one of the threads in which Yamamoto held a meeting with Yamaguchi to discuss signals security and use of deception. ITTL Yamaguchi had survived Midway and was commander of the KB, training up in either Hokkaido or the Kuriles when he was called to confer with Yamamoto regarding its future employment. The thing was that the ideas in the post intrigued me, and the niggle has persisted despite my health issues, but it's taken me till now to catch up and try and pursue it further. The trouble is with cancer and radiation therapy I've lost track of the original post or thread that initiated this niggle, and now I can't find it. I'm wondering if anyone out there can recall a similar post or thread to point me too. I know it's a long shot but if anyone has some ideas or recalls the narrative described I'd appreciate it if you can direct me to possible posts. Thanks for any assistance I hope to hear from people regarding anything remotely like this. Tks T.

Sorry that this isn't what you really wanted, but you might find it interesting. I'm sure the issue has come up of the IJN changing their codes. They did change them periodically, but the new versions were based on the same basic code with numerical add-ons. It took some time to crack the new JN-25 code and for that time USN signal intel was blind.

Both the Germans and Japanese were confident that the complexity of their codes and coding systems made them very secure. The IJA codes were very hard to break, and the Americans didn't have any success until April 1943. In early 1944 the Australians were lucky to find coding equipment and code books that the Japanese army had failed to destroy. The German Navies Triton code was only broken when the British managed to capture a Triton code book from a sinking U-Boat.

Welcome back Tangles2 and I hope your recovering from your health issues. Good luck.

 

[Tangles2]

Sorry that this isn't what you really wanted, but you might find it interesting. I'm sure the issue has come up of the IJN changing their codes. They did change them periodically, but the new versions were based on the same basic code with numerical add-ons. It took some time to crack the new JN-25 code and for that time USN signal intel was blind.

Both the Germans and Japanese were confident that the complexity of their codes and coding systems made them very secure. The IJA codes were very hard to break, and the Americans didn't have any success until April 1943. In early 1944 the Australians were lucky to find coding equipment and code books that the Japanese army had failed to destroy. The German Navies Triton code was only broken when the British managed to capture a Triton code book from a sinking U-Boat.

Welcome back Tangles2 and I hope your recovering from your health issues. Good luck.

Tks, but it wasn't just the codes, it was also some of the deception and signal security issues that I liked to consider. Moving sigs and the different hands being used and relocating different ships etc. Just was a nice little summary I wanted to revisit from memory. Tks T.

 

[Spherical_light]

I've considered this topic myself a bit, not their discussions of it, but that Yamamoto would test to see if the codes were compromised by sending out what are effectively false flag messages and ascertaining the allies responses.

My own thinking revolves around the use of special code words or phrases to indicate a test message.

Example [that is my own thinking rough translation] "Yalu, Yalu, Kaiju. Looking toward NC. Pies are baking."

You might notice that this sample message phrase is derived from something I saw on US code mentioning that they put odd phrases on the end of the messages. However, my thinking for the Japanese codes are something like so: A word repeated 3 times at the start means a legit message, If it is two words followed by a wildlife word like above, then the message is a test message. The middle part references New Caledonia, and the last part is a semi-random phraseology.

Please note that I have no idea how coded messages really work and that this is based on my own conjecture. I do realize that changing codes and how an organization communicates is a very painful process to undertake, certainly the IJN did not like to change codes if it could be helped, any of the navies likely hated having to change communication codes.

As for Yamamoto and Yamaguchi discussing codes, I'm unaware of such a thread myself. Perhaps try searching this forum with "codes" and see if it pops up that way?

 

[Carl Schwamberger]

Please note that I have no idea how coded messages really work and that this is based on my own conjecture. I do realize that changing codes and how an organization communicates is a very painful process to undertake, certainly the IJN did not like to change codes if it could be helped, any of the navies likely hated having to change communication codes.

One of the reasons code breakers are able to penetrate back into a code change is invariably some enemy station does not receive the new books/keys/bigram table, or whatever on schedule. They are forced to send message in the old code, which invariably gives clues into the the new. Just regular monthly or quarterly changes in something simple like key settings are difficult to execute.

The Japanese tended to change their key settings for the senior command radio code every three months, or shortly before starting a major operation. This is what the USN labeled the JN-25 code. In March 1942 such a change occurred, which confounded USN reactions to the Coral Sea battle. However the carrier raid on Tokyo caused a mass of radio traffic among the Japanese home fleet for several days. These messages were composed and sent in a state of borderline panic because of the raid. Errors in encryption and sloppy radio discipline gave the US codebreakers a number of cribs to use to break back into the JN-25. Had the raid not occurred, or had the Japanese signals officers enforced proper practice and discipline the USN may have still been blind in May as the Japanese Midway operation approached.