Blockchain Sharding and Incentive Mechanism for 6G Dependable Intelligence

The sixth generation(6G) wireless communication network will become the base of endogenous intelligence,ubiquitous connectivity,and full-scene interconnection.It is an important basis to realize dependable intelligence in the future.Blockchain is considered as the key decentralized-enabled technology to improve the performance of 6G networks.In the future,the consensus nodes of the blockchain will be composed of massive edge devices and connected through wireless networks.However,motivating self-interest edge devices to participate in the consensus process still faces the challenges of information asymmetry,resource constraints and heterogeneous wireless communication environment.To solve these challenges,a blockchain sharding framework and an incentive mechanism for trusted and dependable intelligence in 6G are proposed.Firstly,an incentive mechanism is presented based on contract theory,which aims to maximize the benefits and reliability of the blockchain sharding.By analyzing the practical byzantine fault tolerance (PBFT) based intrashard consensus mechanism,this paper design energy consumption model for auditing and transmitting the blocks in wireless networks.Secondly,in order to improve the system reliability,it proposes a reputation mechanism based on subjective logic.Finally,a set of optimal contracts under complete information and asymmetric information scnearios are abtained,which could optimize the block revenue for blockchain service requester,while ensuring some desired economic properties,i.e.,budget feasibility,individual rationality and incentive compatibility.Simulation results show that the proposed contract-based incentive mechanism can motivate edge devices to participate in the blockchain consensus process and maintain the operation of blockchain from the perspective of economics more efficiently