Code of the Week!

view of the enigma machine

For your chance to win your very own signed copy of Simon Singh's Code Book try out your codebreaking skills with the "Code of the Week".

Solution for the "Code of the Week!" week starting 17th December 2007

Week 5 "Name the Band"

A British girl pop group formed in London. Their debut single is "Wannabe" and have recently reunited after separating seven years ago.

The Spice Girls

Code of the Week 5 (week starting 17th December 2007)

Digraph Cipher 

A digraph is a pair of letters used to represent a single letter. For example, "NG" can be used to represent "B".  

A digraph cipher encrypts by substituting each digraph in the message with a different digraph or symbol.  

Example:  

Plaintext: DIGRAPH CIPHER

The plaintext letters are split into pairs: DI GR AP HC IP HE RX 

If there is an odd number of letters, the letter "x" is used as a "dummy" letter to complete the pair. 

"DI" is encrypted by finding the intersection of the column headed by "d" with the row headed by "I" which gives "QY"

"GR" is encrypted as "TP" (column "T", row "P")

The ciphertext would be: QY TP NR UE VR UC EJ

For more information on the digraph cipher see http://www.simonsingh.net/The_Black_Chamber/digraphcipher.htm

digraph cypher
Follow this link for a larger version of the digraph key

Using the digraph key above, decipher this week's cipher.  

Good luck!

"Name the band"

Ciphertext 

NF EY GY FZ TY EV CS CA ES HT SS EU RD VT YS AD BT. GZ RY ED RF HN FY AA YC VO "JG AT NF R"G AD VG IC EC PC AN YI EC HT VN RD NB GC EO RR NP NN VT TO RL RT LC NP FG TS.