Twin-chain PBFT consensus for blockchain-based Non-Terrestrial Networks

Blockchain-based non-terrestrial networks (NTN) are expected to ensure the reliability of data in the process of data sharing between untrusted entities. Nevertheless, the low transactions per second (TPS) of blockchain makes it unable to support a large number of data sharing tasks in NTN. One of the key factors for low TPS is the single-chain structure of blockchain. In this way, block generation and block verification are only permitted to be executed sequentially, that means only a single valid block can be generated in the same period. To resolve this dilemma, we propose a twin-chain practical byzantine fault tolerance consensus strategy (TPBFT), in which the consensus process is executed in parallel at two aspects. The first parallel aspect permits block generation and block verification being executed in parallel by twin-chain structure. The second parallel aspect is that the block can be generated with sub-blocks being generated in parallel by replacing transactions with sub-blocks. Finally, the effectiveness of TPBFT is verified by simulation, and the TPS can reach up to 3×10 ⁹ , which means the problem of low TPS of blockchain-based NTN is solved.