Design of Low-latency Overlay Protocol for Blockchain Delivery Networks

Abstract

A major concern of blockchain systems is to scale up their throughput. Many improvements and novel consensus protocols have been proposed to address this issue, but they are intrinsically limited by the message synchronization latency of the underlying peer-to-peer (P2P) network. Most existing implementations of blockchain systems are based on the unstructured random overlay disseminating networks, which often results in a heavy-tailed delivery latency distribution, impairing the decentralization property of the blockchain system. To overcome these constraints, this research proposes Urocissa, a structured overlay protocol to reduce the delivery latency and to improve steadiness for blockchain systems. By exploiting the unique characteristics of blockchain traffic and network heterogeneity, the protocol maintains multiple minimum latency broadcasting trees in a distributed way, whereby each node communicates with its neighbors and makes decisions sovereignly to balance relaying tasks among participants. Experiments show that the proposed protocol significantly reduces block delivery and confirmation latency compared to the conventional blockchain delivery network protocols.