entropy extraction in metastability-based trng presented by cheng chung wang & hsi shou wu 1
TRANSCRIPT
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Background
• TRNG : True Random Number Generators• Entropy : Natural Sources– Cosmic rays– Stray electromagnetics waves– Thermal noise
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Background cont’d
• Process variation and operating condition will impact the output of TRNG circuits
TRNG1
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Temperature
Fabrication defect
Operating voltage
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Motivation
• Several proposed biased removal circuit.• Which one is the best solution?• “Action speaks louder than words”
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Implementation and analysis
Drawback:1. not generate at const rate!2. Effective bit rate decrease with technology scaling
• With Von Neumann correctorEnhance entropy a lot
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Implementation and analysis
• TRNG with calibrationIncrease entropy but remain const output rate
Less energy overhead
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Implementation and analysis
• TRNG with calibrationTradeoff between number of bits entropy and energy consumption
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Conclusion
• 1. Modern security systems need on-chip true random number generators.
• 2. Conventional post-processing techniques are not efficient for simple TRNG – Physical calibration techniques are required .– provide a greater flexibility for trading off entropy
for energy
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Discussion
1. Is the referenced model (dual inverter) representative?
2. Will the results change if we also run Monte Carlo simulation in other parameters (temperature or voltage drop)?
3. Would the area overhead be a huge issue?4. As technology scaled down, dose the experiment
result still make sense?5. Is bit generation rate a more important issue?