Vigenère cipher

January 5, 2017
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A Tabula Recta or Vigenère Square used with a password to crack the cipher

A powerful cipher that uses a keyword to create a series of Caesar ciphers — difficult to solve without the keyword, and easy if you have it.

A Caesar cipher shifts letters in the alphabet by a determined number, so ABCD with a shift of 3 would become DEFG.  The Vigenère uses several different Caesar shifts based on a keyword.  The keyword (e.g. Password) is repeated over and over again during the message (e.g. passwordpasswordpasswor…).  Each letter is paired with the encrypted message to produce a different shift based on a tabla recta — shown above and easily replicated.  As a result, the letter z might mean an t at one point in the code but it might mean an h at another point.  Without the keyword (or at least knowledge of how long the word even is), it is nearly impossible to crack.

According to Wikipedia, the cipher dates back to 1553 in the writing of crypologist Giovan Battista Bellaso but was incorrectly attributed to Blaise de Vigenère and named for him.

This was another cipher taught to me by the great minds behind the Mystery Experiences Company.

 

 


Knock-knock jokes

January 3, 2017

mans hand using door knocker on wood effect upvc door cold calling household

The knock-knock joke is the fad that never died.  This form of humor, neither inherent to language like the pun (which it relies heavily upon), nor inherent to human nature like sarcasm must have had a birthdate.  At the very least, it could not be older than since man lived behind closed doors.  Thankfully, the good folks at Wikipedia had already done their homework on this.

Here are the relevant facts:

  1. Before the knock-knock joke according to NPR was the “Do You Know?” joke.  As in, “Do you know Arthur?” “Arthur Who?” “Arthurmometer!”  This sort of nonsense was around at the turn of the 20th century.
  2. In 1936 the Knock-knock joke took off, appearing everywhere.  This undoubtably was the year it became a thing.  Also that year that Republicans nominated Col. Frank Knox as their vice-presidential nominee.  NPR suggested the two events were not unrelated.
  3. By the end of that year, it was already annoying, but still it lived on.
  4. According to a comedy sketch that year, it was invented by a fictional character named Ramrod Dank.  I just needed to include that name.

Dancing Men Cipher

December 31, 2016

Also known as a Sherlock Cipher, this basic code comes from the Sherlock Holmes story “The Adventure of the Dancing Men.”  It is a very basic substitution cipher but with fun little Keith Haring men. The end of words was signified with tiny flags in the men’s hands.

Wikipedia lists the story as Arthur Conan Doyle’s third favorite.

 


Rail Fence Cipher

December 30, 2016

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A transposition cipher written in a zigzag that simulates the pattern of rails on a fence.

A few months ago, I gave in and clicked on a persistent facebook ad for the Mystery Experiences Company.  At the risk of sounding like an infomercial, it sends me a new puzzle story every month with lots of cool props and was totally worth it.  At the very least, I have learned a ton about cryptography, which will be the subject of several new posts.

This cipher works by writing out a message on a “rail fence” of a set number of posts, descending then ascending in a zig-zag fashion.  So the message: “This is a cipher” might look like this in a three rail cipher:

T—I—P—

-H-S-A-I-H-R

–I—C—E

The code then is created straight across, top to bottom.  So in the case above: TIPHSAIHRICE.

It is not considered a particularly difficult cipher to break once identified as a rail fence cipher, because one would only need know the number of “rails.” One tip that is is a rail fence cipher is that because it is simply an anagram, the frequency of letters will remain consistent with the rest of the English language.

Some information about Rail Fence Ciphers was found at Sophia Knight’s page at Trinity College: http://www.cs.trincoll.edu/~crypto/historical/railfence.html


Stellenbosch

February 8, 2014

Stellenbosch, South Africa, a beautiful town to visit, but a terrible place to be assigned.

Transitive verb: To assign someone incompetent to a position of little responsibility

I don’t like lifting words from Anu Garg’s wonderful A.Word.A.Day but this was simply too good.  Stellenbosch is was a city in South Africa where British officers  with little experience or talent were sent during the Second Boer War.

 


Anodyne

January 18, 2014

Adj: Not likely to cause dissent or offense.

Found in J.K. Rowling’s the Cuckoo’s Calling.  Coming from a scientific name for a painkiller, the phrase is used for something so milquetoast that it is unlikely to upset any applecarts.

 


Dead-cat Bounce

December 10, 2013

Dead-cat Bounce

NBA Writer Matt Moore used this phrase to describe the Brooklyn Nets victory over the Milwaukee Bucks, but the phrase comes from the world of finance.  It is used to describe a small temporary jump in a stock in the middle of a disastrous decline.  The naive will see this as recovery and unwisely buy.

There does not seem to be any consensus as to whence the phrase originates, but the idea is that even a dead cat will bounce if you drop it from high enough.  It first seems to have been used in print in a 1985 Financial Times article by Chris Sherwell.