Stream Cipher Performance and Security Evaluation on ARX-Based Stream Ciphers
4Rounds to Full DiffusionSalsa20
Evaluation Results
| Method | Links | ||||||
|---|---|---|---|---|---|---|---|
| Salsa20State Size / Structure=4×4 state, 512-bit, Quarter-Round Function (QR-F)=ARX with rotation constants (7, 9, 13, 18), Primary Security Enhancement=Baseline ARX design, Practical Deployment=Implemented in some legacy protocols (TLS 1.2 cipher-suites)2026.04 | 4 | — | 8 | — | 3 | 4 | |
| ChaCha20State Size / Structure=4×4 state, 512-bit, Quarter-Round Function (QR-F)=ARX with rotation constants (16, 12, 8, 7), Primary Security Enhancement=Reordered QR-F for better diffusion, Practical Deployment=Widely deployed (TLS 1.3, WireGuard, QUIC)2026.04 | 3 | 20 | 20 | 50 | 3.3 | — | |
| XChaCha20State Size / Structure=4×4 state, 512-bit (with 192-bit extended nonce), Quarter-Round Function (QR-F)=Same as ChaCha20, Primary Security Enhancement=Larger nonce for key reuse resistance, Practical Deployment=Deployed where nonce misuse resistance is critical (libsodium, TLS variants)2026.04 | 3 | 20 | 20 | 20 | 3.3 | — | |
| EChaCha20 with StringologyState Size / Structure=6×6 state, 1152-bit matrix, improved diffusion coverage, Quarter-Round Function (QR-F)=Extended QR-F with six ARX rotations (16, 12, 8, 7, 4, 2) for enhanced diffusion, Primary Security Enhancement=Increased state size, extra rotation constants, and additional rounds strengthen resistance to differential and rotational attacks, Practical Deployment=Drop-in replacement for ChaCha20; suitable for modern TLS/VPN/embedded systems with enhanced security2026.04 | 3 | 3 | 100 | 2 | 3.6 | 6 |