AES-256
Definition
AES-256 is the Advanced Encryption Standard with 256-bit keys, the gold standard for symmetric encryption. Adopted by NIST in 2001, AES-256 encrypts data efficiently and resists quantum attacks—Grover's algorithm reduces security to 128 bits, which remains computationally infeasible to break.
Technical Explanation
AES is a block cipher processing 128-bit blocks through substitution-permutation networks. AES-256 uses 14 rounds of transformation with a 256-bit key. Operations include SubBytes (S-box substitution), ShiftRows, MixColumns, and AddRoundKey (XOR with key schedule).
Classical brute force requires 2²⁵⁶ operations—impossible. Grover's algorithm reduces this to 2¹²⁸ quantum operations—still impossible with any foreseeable technology. AES-256 is considered quantum-safe for symmetric encryption.
SynX Relevance
SynX uses AES-256 for symmetric encryption operations: wallet file encryption, secure communication channels after key establishment, and data protection. Kyber-768 establishes quantum-resistant shared secrets that key AES-256 encryption, providing end-to-end quantum security.
Frequently Asked Questions
- Is AES-256 overkill?
- For quantum resistance, no—128-bit post-quantum security is the target, which AES-256 provides after Grover's reduction.
- Is AES-128 quantum-safe?
- Borderline—64-bit quantum security is weak. AES-256 is recommended for post-quantum applications.
- How fast is AES-256?
- Modern CPUs have AES-NI instructions enabling gigabytes-per-second throughput.
Quantum-safe symmetric encryption. Complete protection with SynX