Performance of Bitcoin Network With Synchronizing Nodes and a Mix of Regular and Compact Blocks

Compact blocks, and compact block protocol are a recent addition to the Bitcoin (BTC) data propagation protocol that aims to reduce bandwidth requirements and, possibly, reduce latency as well. In this work we evaluate operation of BTC network under a mix of regular, and compact block traffic, assuming that nodes randomly leave, and re-join the network, and perform block and, optionally, transaction pool (mempool) synchronization upon returning. Our analysis begins by evaluating block, and transaction deficits accumulated during the node absence and block synchronization. Then, we analyze mempool behavior, and show that mempool synchronization is necessary since it decreases probability of transaction deficit, and the need for transaction retrieval actions. Finally, we analyze the impact of synchronization activities, and transaction deficit on data distribution times in the BTC network with high, and low bandwidth distribution modes for a mix of compact, and regular blocks. Results demonstrate resilience to node absence, and subsequent synchronization, as well as substantial performance improvements for small protocol changes. Furthermore we show that the low bandwidth mode is more resilient to potential security attacks.