WHITE PAPER: The Reliability of SRAM PUF

SRAM PUF Bit Error Rates

Open

Open

Key Extraction from SRAM PUF

Key Reliability

A key generation fails when the key extractor is unable to correct all the PUF response bit differences that
simultaneously occur in a single evaluation. The key failure rate is the probability of this happening and should be very small for practical applications (typically smaller than 10−9).

By combining the SRAM PUF anti-aging (Part A) with error correction algorithms as explained in the previous
section, the Intrinsic ID SRAM PUF implementation is designed to reconstruct a key with a failure rate of less than 10-9 even under extreme conditions when the noise in the PUF would rise up to 25%.

This has been tested by running 10 billion 256-bit key reconstructions on simulated SRAM PUF data (of 1KB)
where 25% noise was introduced. The results indicated only four key reconstruction failures. Note that in a
realistic situation the SRAM PUF noise levels will often be lower than 10% and the key reliability will even be
much better and the failure rate much less than 10-9.