ScaloWork: Useful Proof-of-Work with Distributed Pool Mining

2025-04-19

AI Summary

Bitcoin’s proof-of-work (PoW) mechanism suffers from excessive energy consumption and computationally unproductive hashing. This paper proposes ScaloWork, a novel framework that replaces hash-based mining with distributed computation of the Minimum Dominating Set (MDS) on graphs—thereby repurposing mining resources toward practically valuable graph analytics. Our contributions are threefold: (1) a graph-isomorphism–based solution extraction mechanism ensuring correctness and efficient verifiability; (2) a distributed, anti-free-riding mining pool protocol enabling scalable parallel MDS solving; and (3) a design jointly optimizing scalability and solution quality. Security is rigorously established via formal modeling and verification. Experimental evaluation on a prototype implementation demonstrates that ScaloWork outperforms the state-of-the-art Chrisimos scheme across all dimensions—solving efficiency, solution optimality, fairness, and security—while fully dedicating computational effort to meaningful graph computation tasks.

Technology Category

• Data Mining & Knowledge Management: Scalability, Parallel & Distributed Systems
• Machine Learning: Scalability of ML Systems
• Search and Optimization: Distributed Search

Application Category

• Economics, Online Markets and Human Computation: Economic aspects of blockchain and cryptocurrencies
• Web Mining and Content Analysis: Content-based information diffusion
• Security and Privacy: Blockchains and distributed ledgers

Abstract

Bitcoin blockchain uses hash-based Proof-of-Work (PoW) that prevents unwanted participants from hogging the network resources. Anyone entering the mining game has to prove that they have expended a specific amount of computational power. However, the most popular Bitcoin blockchain consumes 175.87 TWh of electrical energy annually, and most of this energy is wasted on hash calculations, which serve no additional purpose. Several studies have explored re-purposing the wasted energy by replacing the hash function with meaningful computational problems that have practical applications. Minimum Dominating Set (MDS) in networks has numerous real-life applications. Building on this concept, Chrisimos [TrustCom '23] was proposed to replace hash-based PoW with the computation of a dominating set on real-life graph instances. However, Chrisimos has several drawbacks regarding efficiency and solution quality. This work presents a new framework for Useful PoW, ScaloWork, that decides the block proposer for the Bitcoin blockchain based on the solution for the dominating set problem. ScaloWork relies on the property of graph isomorphism and guarantees solution extractability. We also propose a distributed approach for calculating the dominating set, allowing miners to collaborate in a pool. This enables ScaloWork to handle larger graphs relevant to real-life applications, thereby enhancing scalability. Our framework also eliminates the problem of free-riders, ensuring fairness in the distribution of block rewards. We perform a detailed security analysis of our framework and prove our scheme as secure as hash-based PoW. We implement a prototype of our framework, and the results show that our system outperforms Chrisimos in all aspects.

Problem

• Replacing energy-wasting hash PoW with useful computations
• Improving efficiency and quality of dominating set solutions
• Enabling scalable distributed mining for real-life graphs

Innovation

• Replaces hash-based PoW with dominating set computation
• Uses graph isomorphism for solution extractability
• Implements distributed pool mining for scalability