An anti-liveness-attack main chain selection mechanism in sharding blockchain

• 1、Beijing Laboratory of Advanced Information Networks, Beijing University of Posts and Telecommunications, Beijing 100876

Abstract：Since the advent of Bitcoin, the underlying blockchain technology has attracted attention in addition to various cryptocurrencies. However, a very important factor restricting the large-scale application of blockchain technology is performance. Low throughput cannot meet actual needs. Sharding solution in blockchain can improve the throughput with the number of shardings. It is also considered as a very promising solution to the performance of the blockchain. But a major challenge is to design an applicable main chain selection algorithm that can guarantee the security of the sharding blockchain. This paper proposes an improved GHOST scheme suitable for sharding blockchain. First of all, the node with a higher weight is more likely to be selected for mining later by constructing a weight chain to record the weight of all nodes, encouraging miners to maintain the system so that they can increase their weight. Secondly, we combine the node weight value with Analytic Hierarchy Process to select the main chain. On this basis, a specific design scheme under the fragmentation scenario is given. The analysis and simulation results show the safety, scalability and decentralization of the scheme we propose.

Keywords： Blockchain, Sharding, Weight, AHP, GHOST