Algorithm Development:
- Designing cryptographic schemes provably secure against both classical and quantum attacks
- Balancing security assumptions with practical constraints
- Limited mathematical foundations compared to classical crypto (RSA, ECC)
Implementation Challenges:
- Much larger key and signature sizes (often 10-100x larger than classical schemes)
- Higher computational overhead for operations
- Side-channel attack resistance is harder to achieve
- Memory constraints on embedded devices
Performance Trade-offs:
- Significantly slower operations in many cases
- Memory usage concerns, especially for constrained devices
- Network bandwidth impact from larger message sizes
- Battery life implications for mobile devices
Standardization & Migration:
- NIST standardization process revealed vulnerabilities in several candidates
- Hybrid approaches needed during transition period
- Legacy system compatibility issues
- Coordinating industry-wide migration
Security Analysis:
- Relatively new algorithms with less cryptanalytic scrutiny
- Quantum attack models still evolving
- Conservative parameter selection leads to larger sizes
Practical Deployment:
- Integration with existing protocols (TLS, VPNs, etc.)
- Hardware acceleration support still developing
- Crypto-agility in systems design