Design and Implement a Quantum Blockchain Framework to Secure 6G Communication for Consumer Applications

The integration of blockchain with 6G networks offers secure, decentralized solutions for emerging consumer applications by addressing key challenges such as device reliability, interoperability, and security. Classical blockchains rely on cryptographic primitives for data integrity and trust, but these are vulnerable to quantum attacks and face scalability challenges in ultra-dense environments. To address these issues, we propose a quantum blockchain framework based on temporally entangled GHZ states, enabling inherent quantum encoding of block linkage and integrity. A four-qubit blockchain data structure is designed and implemented using IBM Q quantum processors, with a quantum hash circuit developed to link consecutive blocks securely. The system’s resilience is validated against two representative quantum attacks, CNOT and Ping Pong, demonstrating its ability to maintain tamper resistance in noisy environments. The experimental results achieved a fidelity of 65.79% and offered greater structural security than classical hash-based chains under similar conditions. This enables secure, scalable, and quantum-resilient blockchain integration for 6G consumer applications such as telemedicine, IoT device authentication, decentralized finance, and immersive edge services.