Golden-Alice-bar

Just like every end of year, I am awarding the Golden Alice for outstanding achievements in the field of crypto history and codebreaking.

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In May 2014 the NSA published four crypto challenges via Twitter. To my knowledge, the fourth one is still unsolved.

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In 1916 an unknown man robbed a ticket counter at the train station of Lima, Ohio. According to a local newspaper he left behind an encrypted message, the purpose of which is unknown. The message has never been deciphered.

Celebrity-Cypher-2-bar

20 years after the last message of the infamous Zodiac Killer an unknown person sent a Zodiac-style postcard to a California newspaper. As far as I know, it has never been deciphered.

Formula-bar

Today’s blog post is not about an unsolved cryptogram. Instead, I need the help from my readers to solve a mathematical problem. The solution might be helpful to break encryptions.

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Three encrypted texts left behind by Nobel Prize winner Richard Feynman are probably the most famous crypto mystery I have never blogged about before. Today, this is going to change.

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Crypto puzzle games in the advent time have a long tradition. Here are two nice ones of this year’s season.

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The Reddit discussion group /r/codes is a forum for cryptographic questions of all kinds. Occasionally, interesting unsolved cryptograms can be found there.

Zodiac-TV-Lego-bar

The fifth episode of HISTORY’s Zodiac Killer documentary revealed an alleged solution of the infamous Z340 cryptogram. Does it make sense?

Zodiac-TV-bar

Four episodes of the Zodiac Killer documentary on HISTORY have aired now. The fourth one ended with Craig Bauer saying that he has broken Z340. Will episode 5 tell us the solution?