Quantum Key Distribution vs Post-Quantum Cryptography

Two approaches exist for quantum-era security: Quantum Key Distribution (QKD) and Post-Quantum Cryptography (PQC). The SynX quantum-resistant wallet uses PQC—here's why.

What Is QKD?

Quantum Key Distribution uses quantum physics:

• Transmit encryption keys via quantum states (photons)
• Any eavesdropping disturbs quantum states
• Provides theoretically perfect security
• Requires specialized hardware

What Is PQC?

Post-Quantum Cryptography uses mathematics:

• Algorithms based on hard mathematical problems
• Runs on standard computers
• Software-only implementation
• NIST-standardized (FIPS 203/205)

Comparison

Why PQC for Cryptocurrency

The SynX quantum-resistant wallet uses PQC because:

• Blockchain operates on standard internet
• Users need global accessibility
• Mobile and desktop deployment required
• No specialized hardware acceptable

QKD Limitations

• Cannot store or forward quantum keys
• Requires direct line of sight or fiber
• Implementation vulnerabilities exist
• Not suitable for decentralized networks

PQC Advantages for Crypto

• Works on any device
• Integrates with existing blockchain architecture
• NIST standardization provides confidence
• Backward-compatible upgrade path

Hybrid Future

Some high-security applications may use both:

• QKD for infrastructure links
• PQC for end-user devices
• Defense-in-depth approach

Frequently Asked Questions

Is QKD more secure than PQC?

QKD has information-theoretic security, but implementation challenges. PQC in the SynX quantum-resistant wallet provides practical, standards-based security — NIST FIPS 203 and FIPS 205, hardened by internal adversarial testing and a public bug bounty, with a full independent audit scheduled at the first halving when the source opens.

Will cryptocurrency ever use QKD?

Unlikely for user wallets. Infrastructure may eventually incorporate QKD for node communication.