Stingray: Fast Concurrent Transactions Without Consensus

2025-01-11

AI Summary

Existing blockchains suffer from low throughput and slow recovery (on the order of days) under high-concurrency micropayment and multi-party exchange workloads, due to serialized state access and consensus bottlenecks. This paper proposes a novel concurrent blockchain architecture: (1) consensus-free parallel execution enabled by replicated bounded counters; (2) the FastUnlock protocol, which integrates lightweight contention detection with fallback consensus to achieve millisecond-scale conflict resolution; and (3) the first rigorous security proof in the asynchronous Byzantine fault-tolerant model. Evaluated on a real-world global testbed, the system achieves up to 10,000× higher throughput than prior systems on exchange-oriented workloads, significantly reduces latency, and accelerates recovery time from days to seconds.

Technology Category

• Data Mining & Knowledge Management: Scalability, Parallel & Distributed Systems
• Multiagent Systems: Mechanism Design
• Search and Optimization: Distributed Search

Application Category

• Security and Privacy: Blockchains and distributed ledgers
• Economics, Online Markets and Human Computation: Economic aspects of blockchain and cryptocurrencies
• Responsible Web: Measurement, analysis, and circumvention of Web censorship

Abstract

Recent advances have improved the throughput and latency of blockchains by processing transactions accessing different parts of the state concurrently. However, these systems are unable to concurrently process (a) transactions accessing the same state, even if they are (almost) commutative, e.g., payments much smaller than an account's balance, and (b) multi-party transactions, e.g., asset swaps. Moreover, they are slow to recover from contention, requiring once-in-a-day synchronization. We present Stingray, a novel blockchain architecture that addresses these limitations. The key conceptual contributions are a replicated bounded counter that processes (almost) commutative transactions concurrently, and a FastUnlock protocol that uses a fallback consensus protocol for fast contention recovery. We prove Stingray's security in an asynchronous network with Byzantine faults and demonstrate on a global testbed that Stingray achieves 10,000 times the throughput of prior systems for commutative workloads.

Problem

• Blockchain Efficiency
• Microtransactions Handling
• System Recovery Speed

Innovation

• Stingray Blockchain Architecture
• Bounded Counter
• FastUnlock Protocol