SELF Chain Post-Quantum Cryptography
Introduction
SELF Chain is implementing a comprehensive post-quantum cryptography (PQC) strategy to ensure long-term security against threats posed by quantum computing advancements. This document provides an overview of our approach to quantum-resistant security and current implementation status.
🚧 Development Notice: Post-quantum cryptography implementation is currently in the design and planning phase. The features described here represent our architectural approach and roadmap.
Multi-Layered Defense Strategy
Our post-quantum security implementation leverages multiple complementary cryptographic approaches:
1. Quantum-Resistant Key Exchange (Kyber)
SELF Chain implements Kyber, a lattice-based key encapsulation mechanism (KEM) selected by NIST as the first standardized post-quantum cryptographic algorithm. Kyber provides:
- Quantum-resistant secure key exchange
- Strong security guarantees based on module learning with errors (MLWE) problem
- Excellent performance characteristics compared to other PQC candidates
- Well-analyzed security properties with conservative parameter selection
Implementation Status: Module structure designed with planned interfaces for both Kyber-768 and Kyber-1024 variants, with Kyber-1024 as the default for maximum security margin.
2. Quantum-Resistant Signatures (SPHINCS+)
To complement Kyber's key exchange capabilities, SELF Chain implements SPHINCS+, a stateless hash-based signature scheme built upon:
- Winternitz One-Time Signatures (WOTS)
- Merkle tree authentication paths
- Purely hash-based security (no number-theoretic assumptions)
- Stateless design for practical blockchain implementation
Implementation Status: Module structure designed with planned interfaces for SPHINCS+-SHA3-256 in both fast (larger signatures) and small (slower generation) parameter sets.
3. Hybrid Cryptographic Approach
During the transition period, SELF Chain employs a hybrid approach that combines:
- Classical cryptography (ECDSA with secp256k1, X25519) for backward compatibility and immediate security
- Post-quantum algorithms (Kyber + SPHINCS+) for forward security against quantum threats
- Versioned cryptographic operations for smooth transition
Security Benefits
This comprehensive post-quantum approach provides several key benefits:
- Long-term Security: Protection against future quantum computing threats
- Defense in Depth: Multiple cryptographic approaches with different security foundations
- Standardization Alignment: Implementation of NIST-approved algorithms
- Adaptive Design: Cryptographic agility enabling continuous algorithm improvements
User Impact
The transition to post-quantum cryptography will be designed to minimize disruption:
- Phased Rollout: Gradual introduction of post-quantum features
- Backward Compatibility: Support for existing applications during transition
- Performance Considerations: Optimizations to manage larger key and signature sizes
Continuous Evolution
SELF Chain's quantum security approach is designed for continuous improvement:
- Threat Monitoring: Active tracking of quantum computing advances and emerging attack vectors
- Regular Updates: Scheduled security reviews and algorithm upgrades as standards evolve
- Community Involvement: Open collaboration with security researchers worldwide
- Iterative Improvements: Incremental enhancements based on real-world deployment experience
Our commitment is not to achieve perfect security once, but to continuously adapt and strengthen our defenses as the quantum computing landscape evolves. This ensures that SELF Chain remains resilient against both current and future threats.
References
- NIST Post-Quantum Cryptography Standardization: https://csrc.nist.gov/Projects/post-quantum-cryptography/post-quantum-cryptography-standardization
- Kyber Algorithm Specification: https://pq-crystals.org/kyber/
- SPHINCS+ Algorithm Specification: https://sphincs.org/
- OpenQuantumSafe liboqs: https://openquantumsafe.org/liboqs/