Section 5
Broken
How each of them actually fell.
4 entries in Broken
The whole register →- Procedure, not mathematicsAlmost every historical break came from how a system was used rather than from the system itself.
- The cribA guessed fragment of plaintext, and how much it gives away.
- Traffic analysisWho is talking to whom, how often, and how much that reveals without reading a word.
- Read for yearsSystems broken quietly and left in service, because the break was worth more than the warning.