Setchain Algorithms for Blockchain Scalability

2025-09-11

AI Summary

To address blockchain scalability limitations imposed by mandatory global transaction total ordering, this paper proposes Setchain—a framework that abandons linear global ordering and instead organizes transactions into unordered epoch sets. It introduces three distributed consensus algorithms and an epoch-proof mechanism to achieve high throughput and low latency while preserving safety. Built atop CometBFT, Setchain integrates batched transaction compression, cryptographic hashing, distributed content retrieval, and BFT-based signature verification to enable efficient lightweight client verification. Experimental evaluation on multi-server clusters demonstrates that Setchain achieves throughput improvements of multiple orders of magnitude over the underlying blockchain, with finality latency under 4 seconds. The framework thus jointly optimizes scalability, security, and verifiability—resolving key trade-offs in permissioned blockchain design.

Technology Category

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

Application Category

• Security and Privacy: Blockchains and distributed ledgers
• Economics, Online Markets and Human Computation: Economic aspects of blockchain and cryptocurrencies
• Search and Retrieval-Augmented AI: Efficiency and scalability of Web search engines

Abstract

Setchain has been proposed to increase blockchain scalability by relaxing the strict total order requirement among transactions. Setchain organizes elements into a sequence of sets, referred to as epochs, so that elements within each epoch are unordered. In this paper, we propose and evaluate three distinct Setchain algorithms, that leverage an underlying block-based ledger. Vanilla is a basic implementation that serves as a reference point. Compresschain aggregates elements into batches, and compresses these batches before appending them as epochs in the ledger. Hashchain converts batches into fixed-length hashes which are appended as epochs in the ledger. This requires Hashchain to use a distributed service to obtain the batch contents from its hash. To allow light clients to safely interact with only one server, the proposed algorithms maintain, as part of the Setchain, proofs for the epochs. An epoch-proof is the hash of the epoch, cryptographically signed by a server. A client can verify the correctness of an epoch with $f+1$ epoch-proofs (where $f$ is the maximum number of Byzantine servers assumed). All three Setchain algorithms are implemented on top of the CometBFT blockchain application platform. We conducted performance evaluations across various configurations, using clusters of four, seven, and ten servers. Our results show that the Setchain algorithms reach orders of magnitude higher throughput than the underlying blockchain, and achieve finality with latency below 4 seconds.

Problem

• Relaxing strict total order to improve blockchain scalability
• Designing three Setchain algorithms using block-based ledgers
• Enabling safe light client interaction with cryptographic proofs

Innovation

• Setchain algorithms for blockchain scalability
• Epoch-based unordered transaction organization
• Hashchain and Compresschain for efficient batching