Region-based Neighbor Selection in Blockchain Networks

Blockchain networks are mainly used in financial verification processes, the most famous of which is the Bitcoin network consisting of a huge number of nodes. Expansion of blockchain technology, however, to other areas, such as healthcare, arts, culture, and entertainment, is being considered internationally. Especially important challenges for ensuring the reliability of blockchain networks and the security of peer-to-peer networks are shortening the block propagation times throughout a blockchain network to reduce fork and preventing malicious eclipse attacks against targeted nodes in a network. Previous methods have tried to increase the block propagation speed at the expense of imposing a higher burden on each node and a higher risk of eclipse attack. This paper proposes a new neighbor selection method based on the neighbor's regional information. That is, each node has a relatively small number neighbors located outside its region. By using this simple method, the distribution of blocks throughout the network becomes faster and the random neighbor selection nature in a blockchain network is kept intact; thus, risk of eclipse attack is low.