Cryptographic Engine Specification

Security Model & Mathematics

How PassCheck models password search spaces, Shannon entropy, crack resistances, and brute-force complexity.

Information-Theoretic Entropy Model

Shannon entropy in passwords estimates the number of bits of randomness. The formula is based on the size of the character pool N and length L:

Raw Entropy (bits) = Length × log₂(Pool Size)

Character Pool Sizes (N):

  • Lowercase alphabet (a-z): 26 characters
  • Uppercase alphabet (A-Z): 26 characters
  • Numeric digits (0-9): 10 characters
  • ASCII Special Symbols: 33 characters
  • Extended Unicode / Emojis: 128+ characters

Pattern Deductions: If a password contains predictable structures such as keyboard walks (qwerty), simple runs (12345), or dictionary roots (password), the effective search space drops precipitously. The effective entropy subtracts penalty bits derived from structural pattern detections.

Simulated Hardware Attack Scenarios in PassCheck

Average number of guesses required to find a password is 2^(E - 1) (assuming an exhaustive search of 50% of the key space).

Massive GPU Cluster (MD5/NTLM)100,000,000,000 hashes/sec

Represents distributed cracking rigs targeting unsalted or fast hashes.

Single High-End GPU (SHA-256)1,000,000,000 hashes/sec

Standard single modern GPU (RTX 4090 class) benchmark.

Modern Slow KDF (bcrypt/Argon2id)10,000 hashes/sec

Industry standard memory-hard key derivation functions.

Online Rate-Limited Attack100 attempts / hour

Simulates web authentication forms with CAPTCHA and IP throttling.