AZDecrypt notes, tips and tricks

Solvers

AZDecrypt's main window has a list of solvers. Each one is a type of hillclimber that specializes in different types of ciphers:

• Substitution
  • Simple substitution ciphers (including homophonic substitution)
• Substitution + columnar rearrangement
  • A combination of simple substitution and moving columns around.
• Substitution + columnar transposition
  • A combination of simple substitution and columnar transposition.
• Substitution + crib grid
• Substitution + crib list
• Substitution + monoalphabetic groups
• Substitution + nulls and skips
  • Tries to figure out if certain symbols in a substitution cipher don't actually contribute towards the plaintext.
  • More info
• Substitution + polyphones
• Substitution + row bound
• Substitution + row bound fragments
• Substitution + sequential homophones
• Substitution + simple transposition
• Substitution + sparse polyalphabetism
• Substitution + units
  • Jarl's note on using this solver on nomenclator type ciphers:
    • After launching the solver a menu will pop up. You can set the Unit as Symbol or Horizontal sequence, the Mode to Replace with new symbols. If selected Horizontal sequence set the Horizontal sequence to 1. The Key length start determines the amount of Symbols or Horizontal sequences to be replaced. And set Replace, # of symbols per instance to 2 if you want to replace symbols with bigrams for example.
• Substitution + vigenere
• Substitution + vigenere word list
• Bigram substitution
• Higher-order homophonic
• Merge sequential homophones

Pangrams

AZDecrypt was not able to solve this cipher with default settings:

ABC DEFGH IJKLM NKO PEQRS KTCJ U VUWX YKZ RUGH QX IKO LFAB NFTC YKWCM VFDEKJ PEZS

The plaintext consists of two pangrams:

THE QUICK BROWN FOX JUMPS OVER A LAZY DOG PACK MY BOX WITH FIVE DOZEN LIQUOR JUGS

Jarl's fix, under "Options -> Solvers":

• Boost Entropy weight to 10
• Click the "Normalize n-gram factor" button

Now it can solve the cipher.

Batch mode

In batch mode (processing multiple ciphers), under default settings, AZDecrypt will not write output files if newly cracked ciphers' scores are not higher than previously cracked ciphers' scores. To change this, set "Output improvements only" to "No" in "Options -> Solvers"

Solving "Ambiguous Caesar shift" ciphers (aka Hafer ciphers or Hafer homophonic ciphers)

Instructions and details on configuring AZDecrypt to solve these kinds of ciphers can be found here.

The description of the encipherment system is here.

Jarlve posted a new version of AZDecrypt that can solve Hafer ciphers here.

Polyphone solver improvements

Jarl has added improvements to the polyphone solver. Details here.