Symmetric Encryption Overview

Symmetric encryption uses the same key for encryption and decryption. The three most widely used algorithms:

AES (Advanced Encryption Standard): NIST-standardized in 2001, used worldwide. Available in 128, 192, and 256-bit key lengths. Hardware-accelerated on modern CPUs.

ChaCha20: Designed by Daniel J. Bernstein. Software-optimized, faster than AES on devices without hardware acceleration. Used by Google for TLS.

Twofish: AES finalist, designed by Bruce Schneier. 256-bit key, unpatented, less widely adopted than AES.

Detailed Comparison

AES-256-GCM: Industry standard, NIST-approved, hardware-accelerated (AES-NI), authenticated encryption. Used by governments, military, financial institutions. Practical weakness: side-channel attacks if implemented incorrectly.

ChaCha20-Poly1305: Excellent software performance, resistant to timing attacks, used in WireGuard and TLS 1.3. Preferred on mobile devices without AES-NI.

Twofish-256: Conservative design, large security margin, less analyzed than AES due to lower adoption. Used in VeraCrypt and some specialized applications.

All three are considered cryptographically secure. The practical differences are in performance, hardware support, and ecosystem adoption.

What ZeroLatch Uses

ZeroLatch uses AES-256-GCM (Galois/Counter Mode) for client-side encryption. This choice provides:

• 256-bit security level (quantum-resistant against Grover's algorithm with 128-bit effective security) • Authenticated encryption (GCM provides both confidentiality and integrity) • Hardware acceleration on modern browsers via Web Crypto API • Widest industry acceptance and regulatory compliance

For users, the algorithm choice matters less than the implementation: client-side encryption, proper key derivation (PBKDF2), and zero-knowledge architecture.