The Bletchley Park 1944 Cryptographic Dictionary formatted by Tony ...

The Bletchley Park 1944 Cryptographic Dictionary formatted by Tony Sale (c) 2001
DECRYPT :
- 27 -
To decode or decipher (a code or cipher message) cryptographically.
DECRYPTION :
The action or process of decoding or deciphering.
DEDUPE :
To remove (normally the less reliable or less complete) duplicate copies
of cipher texts from (a quantity of traffic), esp. before Freeborning.
DELIVERY GROUPS :
Code groups for route instructions and addresses of code and cipher
messages.
DE-PSI, v :
(used for). To set the psi-wheels in a Tunny message with the help
of machines after it has been de-chied.
DEPTH :
1. A series of code messages reciphered with the same, or the same part
of a, reciphering key especially when written under one another so
that all the groups (usually one in each message) that are reciphered
with the same group of the subtractor lie under each other and form
a 'column'.
(b) two or more messages in a transposition cipher that are of the
same length and have been enciphered on the same key;
(c) two or more messages in a machine or similar cipher that have
been enciphered on the same machine-setting or on the same key.
2. be in depth : (of messages). Stand to each other in any of the
relationships described above.
DEPTH CHART :
A diagram showing the position of (reciphered code) messages on the
key, and thus indicating the depth at any given point.
DEPTH-CRIBBING :
(in Enigma) = Fun and Games .
DERECIPHER :
To strip off the subtractor or other form of recipherment from a reciphered
message.