Viewing Single Post From: Double cipher challenge

Viewing Single Post From: Double cipher challenge
catish10	Aug 12 2007, 06:09 PM
Just registered Posts: 11 Group: Members Member #1,158 Joined: July 29, 2007	Hi I think I can rule out substitution followed by transposition because of the frequencies Histogram Analysis of <Unnamed1>. File size 329 bytes. Descending sorted on frequency. No. Substring Frequency (in %) Frequency 1 P 7.3077 19 2 C 6.1538 16 3 R 5.7692 15 4 G 5.3846 14 5 K 5.3846 14 6 S 5.3846 14 7 Z 5.3846 14 8 W 5.0000 13 9 A 4.6154 12 10 D 4.6154 12 11 T 4.6154 12 12 B 3.8462 10 13 H 3.8462 10 14 I 3.8462 10 15 M 3.8462 10 16 Q 3.8462 10 17 U 3.4615 9 18 V 3.4615 9 19 Y 2.6923 7 20 F 2.3077 6 21 O 2.3077 6 22 L 1.9231 5 23 N 1.9231 5 24 X 1.9231 5 25 E 0.7692 2 26 J 0.3846 1 From what I seem to remember reading in 'Cryptanalysis' a Vig cipher will yield this sort of frequencies. They are pretty flat, compared to English. I do however know from an e-mail I received from the person doing the challenge that there is a keyword involved. I suppose I'll have to look at vig + transpositions now! Michelle


Double cipher challenge · Challenges