## TENTATIVE LIST OF ENIGMA AND OTHER MACHINE USAGES 30 March 1945## Page 9 |
Tony Sale's Codes and Ciphers |

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- 29 March 1945 page 9

The CCM is a wire wheeled enciphering machine. Ezicipherment

is through a normal alphabet input, one-way through five

wheels, and through a normal alphabet output. Each side of

each wheel has an even number of notches, from eight to six-

teen. Let us number the wheels 1, 2, 3, 4, 5 from left to

right. The middle wheel (#3) steps every time. Wheel 4

moves under the influence of the notches on the right side

of wheel 3, and wheel 5 under the influence of the notches on

the right side of wheel 4. Similarly, 2 is influenced by the

left notches of 3 and 1 by the left notches of 2. A wheel

steps if and only if a notch of its governing wheel is in the

active position. The five wheels are chosen from a set of

ten and may be inserted straight or in reverse. There are

thus 20 x 18 x 16 x 14 x 12 = 967,680 wheel orders.

For a known wheel order, the attacks are relatively simple

and could be run on a grenade, on Hypo, or by IBM techniques.

No equipment and no mode of attack are known for unknown

wheel orders, at least in any operational sense.

TOP SECREI

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