Thomas Jefferson's cipher message from Robert Patterson For more than 200 years, buried deep within Thomas Jefferson's correspondence and papers, there lay a mysterious cipher -- a coded message that appears to have remained unsolved. Until now.... To Mr. Patterson's view, a perfect code had four properties: It should be adaptable to all languages; it should be simple to learn and memorize; it should be easy to write and to read; and most important of all, "it should be absolutely inscrutable to all unacquainted with the particular key or secret for decyphering." [more inside]
posted by caddis on Jul 2, 2009 - 22 comments

In March 2007, the FermiLab Office of Public Affairs in Batavia, IL "received a curious message in code" via USPS. In May 2008, scientists posted a facsimile image of the letter to their blog in the hopes of soliciting cryptologists to decipher the letter. [more inside]
posted by subbes on Jul 16, 2008 - 45 comments

A previously unbroken Enigma code has been solved by a group of hackers. After just over a month of effort, the M4 group, using distributed computing, cracked a 60 year-old German naval code. The message: "Forced to submerge during attack." There are lots of other interesting historical codes that still remain mysteries, however. Lots of Enigma goodness in an earlier post.
posted by blahblahblah on Feb 27, 2006 - 16 comments

You've probably heard of the WWII Navajo "code talkers" who managed to baffle crack Japanese cryptanalysts and were credited with enabling US success at Iwo Jima. Civil engineer, journalist and photographer Philip Johnston was the determined mind behind the "windtalkers". The son of missionaries, Johnston grew up on a Navajo reservation and was one of only a handful of outsiders fluent in the Navajo language. A bit of his background is included this article, and you can read a complete history of his plan, view an archive of photos by Johnston, and see copies of his enlistment application letter to the Marine Corps commandant, as well as a recommendation letter from the Commanding General. (more inside...)
posted by taz on Jan 22, 2003 - 13 comments

The Key Vanishes: Scientist Outlines Unbreakable Code [NEW YORK TIMES - free reg required]
In essence, the researcher, Dr. Michael Rabin and his Ph.D. student Yan Zong Bing, have discovered a way to make a code based on a key that vanishes even as it is used. While they are not the first to have thought of such an idea, Dr. Rabin says that never before has anyone been able to make it both workable and to prove mathematically that the code cannot be broken.
 
Once this gets out, the debate on exporting strong crypto would seem to be essentially over.
posted by mikewas on Feb 20, 2001 - 10 comments