Entropy

Definition

Entropy measures randomness or unpredictability in data, essential for cryptographic key generation. High entropy means data is truly random and unguessable. Post-quantum cryptography requires adequate entropy for key generation to resist both classical and quantum attacks.

Technical Explanation

Entropy sources: hardware random number generators (CPU instructions like RDRAND), operating system entropy pools (/dev/urandom), and physical randomness (radioactive decay, thermal noise). True randomness cannot be predicted even with unlimited computation.

Entropy requirements: symmetric keys need bits equal to security level (256 bits for 256-bit security). Quantum attacks on RNG: Grover's doesn't help predict true randomness. Post-quantum key generation needs same entropy as classical—just larger keys.

SynX Relevance

SynX wallet key generation requires high-quality entropy—256+ bits from cryptographic RNGs. Kyber-768 and SPHINCS+ key generation use OS-provided randomness. Low-entropy environments should use additional entropy mixing. Your key security depends on generation-time randomness.

Frequently Asked Questions

How do I ensure good entropy?: Use updated operating systems with hardware RNG support. Don't generate keys on low-entropy embedded devices.
Can quantum computers predict random numbers?: No—true randomness is physically unpredictable. Quantum computers can't predict quantum randomness either.
What's the difference from randomness?: Entropy quantifies randomness in bits. 256-bit entropy means 2²⁵⁶ equally possible values.

Cryptographically random key generation. High-entropy wallets with SynX