Table 3.
Security benchmarking of QuantumShield-BC and classical blockchain under simulated quantum attack scenarios and adversarial conditions.
| Attack type | Evaluation metric | Classical blockchain | QuantumShield-BC |
|---|---|---|---|
| Shor’s algorithm | Private key recovery Time (simulated) | < 10 s (ECDSA 256) | Not applicable (PQC secure) |
| Grover’s algorithm | Effective hash strength (bits) | ~ 128 (SHA-256 halved) | ~ 256 (Keccak/SPHINCS+) |
| Sybil attack | Node infiltration success rate (%) | 60% | 0% (all unauthorized rejected) |
| Replay attack | Duplicate acceptance rate (%) | 35% | 0% |
| MITM on key exchange | Key tampering detection rate (%) | 15% | 100% (detected via QKD) |
| Validator authentication | Forged validator acceptance (%) | 40% | 0% |