Conference：51st International Conference on
Very Large Data Bases
CCF level：CCF A
Categories：Database/Data Mining/Content Retrieval
Year：2025
Num：4
Conference time：London, United Kingdom - September 1-5, 2025
区块链论文速读 CCF A--VLDB 2025 (1) 附pdf下载
3
Title:
Optimal Sharding for Scalable Blockchains with Deconstructed SMR
基于解构式SMR的可扩展区块链最优分片
Authors:****
Abstract:****
Sharding enhances blockchain scalability by dividing nodes into multiple shards to handle transactions in parallel. However, a sizesecurity dilemma where every shard must be large enough to ensure its security constrains the efficacy of individual shards and the degree of sharding. Most existing solutions therefore rely on either weakening the adversary or making stronger network assumptions. This paper presents Arete, an optimally scalable blockchain sharding protocol designed to resolve the dilemma based on an observation that if individual shards can tolerate a higher fraction of Byzantine faults, we can securely create smaller shards in a larger quantity. The key idea of Arete, therefore, is to improve the security resilience of shards by dividing the blockchain's State Machine Replication (SMR) process. Like modern blockchains, Arete first decouples SMR in three steps: transaction dissemination, ordering, and execution. However, for Arete, a single ordering shard performs the ordering task while multiple processing shards perform the dissemination and execution of blocks. As processing shards do not run consensus, each of those tolerates up to half compromised nodes. Moreover, the SMR process in the ordering shard is extremely lightweight as it only operates on the block digests. Second, Arete considers safety and liveness against Byzantine failures separately to improve the safety threshold further while tolerating temporary liveness violations in a controlled manner. Apart from creating more optimal-size shards, such a deconstructed SMR scheme empowers us to devise a novel certify-order-execute architecture to fully parallelize transaction handling, thereby significantly improving the performance. We implement Arete and evaluate it on the AWS environment by running up to 500 nodes. Our results demonstrate that Arete outperforms representative sharding protocols in scalability, throughput, and cross-shard latency without compromising on intra-shard latency.
分片通过将节点划分为多个分片来并行处理交易，从而增强区块链的可扩展性。然而，由于每个分片必须足够大才能确保其安全性，因此存在一个"规模-安全"两难困境，这限制了单个分片的有效性和分片的程度。因此，大多数现有解决方案依赖于削弱攻击者或做出更强的网络假设。本文提出了一种名为 Arete 的区块链分片协议，该协议旨在解决上述两难困境。其设计基于以下观察：如果单个分片能够容忍更高比例的拜占庭故障，我们就可以安全地创建更多更小的分片。因此，Arete 的核心思想是通过拆分区块链的状态机复制 (SMR) 过程来提高分片的安全弹性。与现代区块链类似，Arete 首先将 SMR 解耦为三个步骤：交易分发、排序和执行。然而，对于 Arete 而言，单个排序分片负责执行排序任务，而多个处理分片则负责区块的分发和执行。由于处理分片不进行共识，因此每个分片最多可以容忍一半的节点被攻破。此外，排序分片中的 SMR 进程极其轻量级，因为它仅操作区块摘要。其次，Arete 将安全性和活性分别考虑，以应对拜占庭故障，从而进一步提高安全阈值，同时以可控的方式容忍临时活性违规。除了创建更优化大小的分片之外，这种解构式的 SMR 方案还使我们能够设计一种新颖的认证-排序-执行架构，从而实现事务处理的完全并行化，并显著提高性能。我们在 AWS 环境中实现了 Arete，并在最多 500 个节点上运行对其进行了评估。结果表明，Arete 在可扩展性、吞吐量和跨分片延迟方面优于典型的分片协议，且不会影响分片内延迟。
Pdf下载链接:
https://www.vldb.org/pvldb/vol18/p2198-zhang.pdf
4
Title:
Authenticated Aggregate Queries with Boolean Range Predicates on Blockchains
基于区块链的布尔范围谓词认证聚合查询
Authors:****
Abstract:****
Blockchains have gained wide adoption for secure data processing. As blockchain data volumes grow, the demand for efficient data analysis, especially aggregate queries, becomes increasingly critical. However, current blockchains lack native support for efficient analytical query processing, forcing users to either maintain full replicas or rely on third-party services without integrity guarantees. In this paper, we propose an efficient framework, Merkle Bloom Filter Tree ( MBFT ), for authenticated aggregate queries that combine boolean keywords and range predicates on blockchains. At its core is a Bloom filter-based authenticated data structure that supports both types of predicates, constructed per block for efficient transaction indexing. For temporal predicates, we optimize time window queries through value pruning and block consolidation. We design a novel Merge Bloom Filter ( MBF ) for space-efficient handling of dynamic sets during query authentication. We provide a theoretical analysis of the storage overhead caused by the Bloom filter's false positive rates. Our framework employs data sketches to support various aggregate operations. Extensive experiments demonstrate that MBFT has improved the query speed by up to 286 × compared to state-of-the-art authenticated query solutions.
区块链因其安全性而被广泛应用，用于数据安全处理。随着区块链数据量的增长，对高效数据分析（尤其是聚合查询）的需求日益迫切。然而，当前的区块链缺乏对高效分析查询处理的原生支持，迫使用户要么维护完整副本，要么依赖缺乏完整性保证的第三方服务。本文提出了一种高效的框架------默克尔布隆过滤器树（MBFT），用于在区块链上进行结合布尔关键字和范围谓词的认证聚合查询。其核心是一个基于布隆过滤器的认证数据结构，支持两种类型的谓词，并针对每个区块构建，以实现高效的交易索引。对于时间谓词，我们通过值剪枝和区块合并来优化时间窗口查询。我们设计了一种新颖的合并布隆过滤器（MBF），用于在查询认证过程中高效处理动态集合。我们对布隆过滤器误报率造成的存储开销进行了理论分析。我们的框架采用数据草图来支持各种聚合操作。大量实验表明，与最先进的认证查询解决方案相比，MBFT 将查询速度提高了 286 倍。
Pdf下载链接: