Quantum Supremacy and the Future of Post-Quantum Cryptography
Evaluating cryptographic systems in the age of quantum computing
The Quantum Threat to Classical Cryptography
Shor’s Algorithm Trivia
Did you know? Shor’s algorithm can factor large numbers exponentially faster than classical computers, potentially breaking RSA-2048 in hours rather than millennia!
Vulnerable Systems
At Risk:
- RSA (Integer Factorization)
- ECC (Discrete Logarithms)
- DH Key Exchange
Secure For Now:
- AES-256 (with sufficient key size)
- Hash-based signatures
Post-Quantum Cryptography Candidates
NIST Standardization Progress
| Category | Leading Candidates | Key Size (approx) | Status |
|---|---|---|---|
| Lattice-based | Kyber, Dilithium | 1-2 KB | Final Round |
| Code-based | Classic McEliece | 1 MB+ | Alternate |
| Hash-based | SPHINCS+ | 8-40 KB | Final Round |
| Multivariate | Rainbow | 100-200 KB | Eliminated |
Implementation Challenges
Performance Trade-offs
Computational Overhead:
- 10-100x slower than RSA for some operations
- Specialized hardware (FPGAs/ASICs) may be required
Key Management:
- Larger keys strain IoT devices
- Hybrid approaches needed during transition
New Attack Vectors:
- Side-channel vulnerabilities
- Hybrid quantum-classical attacks
Quantum Threat Timeline
Quantum Computing Milestones
Breakthroughs
- Shor’s Algorithm: 1994, 1 year
- First 5-Qubit Device: 2000, 1 year
- Quantum Supremacy Claim: 2019, 1 year
Projections
- RSA-2048 Break: 2030, 1 year
- Full PQC Transition: 2035, 3 years
Recommended Migration Strategy
Prioritize Systems:
- Long-term data storage first
- Critical infrastructure next
Hybrid Approach:
- Combine classical and PQC algorithms
- Gradual phase-out of vulnerable systems
Continuous Evaluation:
- Monitor quantum computing progress
- Update standards as needed
