Bit Security

Definition

Bit security measures the computational effort required to break a cryptographic system. A scheme with n-bit security requires approximately 2^n operations to break. 128-bit security is standard; 192-bit and 256-bit provide higher margins.

Technical Explanation

Classical bit security assumes attacks run on classical computers. Quantum bit security accounts for quantum speedups—Grover's algorithm halves symmetric cipher security (AES-256 drops to 128-bit quantum), while Shor's algorithm completely breaks RSA and ECC regardless of key size.

NIST defines security levels: Level 1 (128-bit classical/AES-128 equivalent), Level 3 (192-bit/AES-192), and Level 5 (256-bit/AES-256). Post-quantum algorithms specify which level they target, with implementations choosing appropriate parameters.

SynX Relevance

SynX targets NIST Security Level 1+ (128-bit post-quantum) for signatures via SPHINCS+-SHAKE-128f and Level 3 (192-bit) for key encapsulation via Kyber-768. These levels provide substantial security margins against both classical and quantum attacks.

Frequently Asked Questions

Is 128-bit quantum security enough?
Yes—it requires 2^128 quantum operations, far beyond any foreseeable capability.
Why not use maximum security always?
Higher security means larger keys and signatures. SynX balances security with practicality.
How does quantum affect bit security?
Grover halves symmetric security; Shor breaks asymmetric crypto entirely.

Proven bit security for the quantum era. Secure with SynX