<div dir="ltr"><br><div class="gmail_extra"><br><div class="gmail_quote">On Wed, Feb 24, 2016 at 11:58 AM, mok-kong shen <span dir="ltr"><<a href="mailto:mok-kong.shen@t-online.de" target="_blank">mok-kong.shen@t-online.de</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"><br>
Codebook appears, if I don't err, to be an antiquitated topic rarely<br>
touched upon in discussions of modern cryptography.<br></blockquote><div></div></div><div class="gmail_extra"><br></div>Absolutely could be and is a critical part.<br>Not antiquated... but often ignored by the press because </div><div class="gmail_extra">they are effective.<br><br>Almost all the interesting silicon design programs have one</div><div class="gmail_extra">or more code names. Some are marketing some are engineering.</div><div class="gmail_extra">Should a company discover their code name in the press they know</div><div class="gmail_extra">that someone was talking in in public or to the media.<br><br>Part of Snowden's big disclosure was the names of programs.<br>Those names now on the internet make finding are validation</div><div class="gmail_extra">of code words and facilitates correlation of rumors. Compartments</div><div class="gmail_extra">of secrets behind a word no longer lead back wit clarity to the short list of</div><div class="gmail_extra">insiders.</div><div class="gmail_extra"> <br>The notable historic model for this is the Japanese encryption of messages in WW2.<br>The messages was encrypted but islands, bases, etc had code names.<br><br>One encrypted sequences of messages indicated an attack on target XYZ.</div><div class="gmail_extra">The American command had no code book to know where XYZ was. A message</div><div class="gmail_extra">was sent in the clear by the Americans that there was a water supply problem.<br>That message was picked up by a listening post and sent back home. It used</div><div class="gmail_extra">the code name XYZ and that XYZ had a water supply problem.<br><br><a href="http://www.sjsu.edu/faculty/watkins/midwaybattle.htm">http://www.sjsu.edu/faculty/watkins/midwaybattle.htm</a><p>...."some in authority that feared the target might be Hawaii or the West Coast. They did not want defense <br>forces assembled at Midway if Hawaii was going to be the target.</p><p><br>"The situation was resolved sending a message to Midway by secure undersea cable telling them to send <br>an unencoded message by radio to Hawaii announcing that their water desalinization plant had failed and <br>that they had only a two week supply of fresh water. Hawaii sent back a message that the replacement plant <br>was on its way. From the flurry of Japanese messages that resulted from this ploy it was obvious that Midway <br>was to be the target."</p><p>All the old school methods apply. Two identical paperback books. find a word, PageLineCount=word or is it LineCountPage</p><p>Recall that Tora Tora Tora was sent in the "clear".<br>All the planning was communicated in person, via encrypted radio message, encrypted hard copy.<br>Not just one code and method: <a href="https://en.wikipedia.org/wiki/Magic_(cryptography)">https://en.wikipedia.org/wiki/Magic_(cryptography)</a><br>The "Post War Debate" section is being replayed ...<br>Despite reading these messages no message said attack Hawaii. There was a handful of<br>messages that in hindsight show that Hawaii was being watched and could be a target.</p><p>The old code books are interesting. Some are data compression. Some transmit secrets.<br><a href="http://howwethink.nkhayles.com/codebooks/texts/">http://howwethink.nkhayles.com/codebooks/texts/</a><br>Text messages and Morris code have a lot in common. Especially when broadcast via twitter<br>or to a group.</p><p><br></p><p><b><span style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:small;font-weight:normal"> -- </span></b></p><div class="gmail_signature"><div dir="ltr"> T o m M i t c h e l l</div></div>
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