QFRA: a quantum forensic readiness architecture for distributed hybrid classical-quantum networks

Hybrid classical–quantum networks introduce new forensic challenges due to quantum state collapse, decoherence and the no cloning theorem. These features invalidate traditional evidence preservation assumptions. Existing digital forensic frameworks lack proactive mechanisms which are capable of ensuring integrity and readiness in such hybrid environments. This paper proposes the Quantum Forensic Readiness Architecture (QFRA) which is mainly a distributed framework. The framework consists of four major components. They are (i) Quantum Evidence Objects (QEOs) for structured quantum metadata representation, (ii) Forensic Entanglement Mapping (FEM) for hybrid event correlation, (iii) a Decoherence Aware Replication Protocol (QEPP) for adaptive evidence preservation and (iv) a post quantum cryptography based distributed ledger for tamper evident storage. QFRA is implemented in a NetSquid based hybrid simulation with a Practical Byzantine Fault Tolerance (PBFT) style quantum-safe ledger. It is evaluated across 10-100 nodes against centralized, blockchain-only, and static replication baselines. Results show that QFRA achieves an Evidence Integrity Ratio above 0.97 and a Forensic Readiness Level above 0.91 at 100 nodes while maintaining synchronization latency below 50 ms. Statistical validation confirms significant integrity and readiness improvements under scaling conditions. These improvements exhibit bounded sensitivity to decoherence and network delay variations. These results demonstrate that proactive, quantum aware forensic readiness can be achieved in hybrid networks without excessive coordination overhead.