In 1914 he published the first recorded solution of the Playfair cipher.

He is known for his ever popular playfair cipher.

The Playfair cipher uses a 5 by 5 table containing a key word or phrase.

A different approach to tackling a Playfair cipher is the shotgun hill climbing method.

Like most classical ciphers, the Playfair cipher can be easily cracked if there is enough text.

The first recorded description of the Playfair cipher was in a document signed by Wheatstone on 26 March 1854.

The Polybius cipher can be used with a keyword like the Playfair cipher.

He was responsible for the then unusual Playfair cipher, named after his friend Lord Playfair.

They ask Thomas, a skilled puzzle-solver, to decode a playfair cipher written in Booth's diary.

In Have His Carcase, the Playfair cipher and the principles of cryptanalysis are explained.

In 1854, Charles Wheatstone came up with the Playfair cipher, a keyword-based system that could be performed on paper in the field.

Recruited to Bletchley Park, and during early 1942 was the head of a small group working on a double Playfair cipher used by German military police.

In the film National Treasure: Book of Secrets, a treasure hunt clue is encoded as Playfair cipher.

Delastelle's work on the four-square cipher was published in a book in 1902, and was a variant on the earlier Playfair cipher.

Despite its invention by Wheatstone, it became known as the Playfair cipher after Lord Playfair, who heavily promoted its use.

Playfair is also remembered for promoting a new cipher system invented by Charles Wheatstone, now known as the Playfair cipher.

As noted in "Have His Carcase", he communicated at that time with British Intelligence using the Playfair cipher and became proficient in its use.

The Playfair cipher or Playfair square is a manual symmetric encryption technique and was the first literal digraph substitution cipher.

The first published solution of the Playfair cipher was described in a 19-page pamphlet by Lieutenant Joseph O. Mauborgne, published in 1914.

The earliest practical digraphic cipher (pairwise substitution), was the so-called Playfair cipher, invented by Sir Charles Wheatstone in 1854.

The novel Have His Carcase by Dorothy L. Sayers gives a blow-by-blow account of the cracking of a Playfair cipher.

In the audio book Rogue Angel : God of Thunder, a Playfair cipher clue is used to send Anja Creed to Venice.

It was developed to ease the cumbersome nature of the large encryption/decryption matrix used in the four-square cipher while still being slightly stronger than the (single-square) Playfair cipher.

Another Signal Corps officer who would make his mark on cryptology was Joseph Mauborgne, who in 1914, as a first lieutenant, had been the first to publish a solution to the Playfair cipher.

A good tutorial on reconstructing the key for a Playfair cipher can be found in chapter 7, "Solution to Polygraphic Substitution Systems," of Field Manual 34-40-2, produced by the United States Army.