Enigma Machine - Design Presentation

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Enigma Machine - Design Presentation

• Group M1
• Adithya Attawar
• Shilpi Chakrabarti
• Zavo Gabriel
• Michael Sokolsky

Wed. Jan 25 Initial Design
Digital World War II Enigma Cipher
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Status

• Finished
• Design selections
• Block diagram for processes
• To Do
• Verilog
• Schematic
• Layout
• Testing
• Simulation

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Design Decisions

• Project Overview
• Implement on chip the functionality of a World
  War II Enigma cipher machine.
• A sophisticated variation on a simple
  substitution code, it involves a string of 9
  letter pair substitutions, some of which change
  for each new character sent through it.
• Must re-create the effect of both the electrical
  and mechanical aspects of the device on chip.
• User must be able to change the configuration.
• We will represent each character as a 5-bit
  number.

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Design Decisions cont.

• Project Overview
• Initial settings are
• 8 Possible wheels (4 bits)
• 3 Wheels (15 bits)
• Plugboard (12 bits)
• Signal travels through plugboard, 3 wheels,
  reflector, back through 3 wheels, back through
  plugboard, illuminates encoded letter.
• Historically significant code, breaking it had a
  significant impact on WWII

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Block Overview
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Block Functions

• Logic Array - 3000 trans.
• Emulates pegboard to swap characters,
  fundamentally a programmable FSM
• Direction Select - 4000 trans.
• Routes the character through 3 of the 8 wheels in
  the correct order, then through the Reflector,
  back through the wheels, and then back to the
  Logic Array
• Wheel Logic - 6000 trans.
• Takes input character and wheel position and
  outputs a swapped character
• Reflector/Registers - 1000 trans.
• Performs a fixed character swap and holds the
  result for the next cycle, to pass back through
  all of the previous logic

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Questions?

• Adding more encryption options?
• The ability to have A-gtA
• Automatic key generation?
• Randomized wheel movement?