Analysis of Compact Block Propagation Delay in Bitcoin Network

Bitcoin is a blockchain-based network where thousands of nodes are directly connected and communicate through a gossip-based flooding protocol. Mined blocks are propagated to all participating nodes in the network through compact block relay (CBR) protocol. Therefore, reducing the block relay time between nodes can reduce the block propagation time to all nodes and ultimately improve the performance of Bitcoin. In order to reduce the block relay time, the delivery time between nodes must be measured and analyzed to find the cause of the delay and provide ways to resolve it. Therefore, in this paper, we measure the CBR time between directly connected Bitcoin nodes and analyze the cause of the relay delay. Our results show that the delivery time delay is affected by whether or not a transaction is requested when assembling the compact block. In addition, the reason for requesting a transaction is due to the transaction propagation method and the characteristics of the transaction itself.