Designing quantum blockchain system integrated with 6G network

The sixth-generation (6G) network utilizes state-of-the-art machine learning technology and obtains high attention, while the fifth-generation (5G) industry is still developing globally. Unfortunately, 6G encounters challenges to achieve performance superiority, such as scalability, massive connection, integrity, and trust. As a result, future network technologies are migrating away from centralized management entities and toward decentralized and distributed ledger technology, such as blockchain. However, the security of the blockchain is based on the computational complexity of solving specific mathematical problems that are impossible to solve on existing computers in real-time. On the other hand, quantum computers can effortlessly translate such problems with easy decryption. As a result, this study presents an architecture demonstrating the integration of quantum blockchain (QBC) with 6G networks. To show the quantum advantage, highly entangled/secured QBC of 5-, 6-, and 7-qubits are used to create the above system's quantum circuits. After circuit optimization, mitigation is executed with the efficiency analysis to show the advantage of the error mitigation approach in recreating the state of the QBC circuit and executing on quantum hardware. Furthermore, quantum algorithms of blockchain smart provenience contracts for the cloud-centric Internet of Things (IoT) are proposed, and corresponding quantum circuits are designed. The possible outcomes from these circuits based on the input transaction information are verified.