Presenting an Innovative and Low-Risk Approach to Prevent 51% Attacks and Improving Security for Proof of Work Blockchains
Ethereum Classic Labs (ETC Labs) and its ETC Core Developer Team, the development and accelerator organization for the Ethereum Classic (ETC) blockchain, today propose Modified Exponential Subjective Scoring (MESS), an effective finality system to prevent 51% attacks. This proposal, in response to the recent 51% attacks and developed by Isaac A., ETC Core Protocol Lead and Client Developer in collaboration with OpenRelay and ChainSafe, has been successful in testing and is scheduled to be available within the next 10 days.
"While developing a solution for ETC, it was important to us that it be low or no impact on existing consensus or sealing rules, concise enough to implement and test quickly, but comprehensively, and not likely to cause damage or expose the network to risks that could potentially outweigh its benefits,” said Isaac A., ETC Core Protocol Lead and Client Developer.
MESS would prevent 51% attacks by treating large block reorgs as suspect and making them prohibitively expensive, removing all profit motive. It would force large reorgs used to launch attacks to have significantly greater difficulty and common ancestor time. For example with MESS implemented, the recent attacks in August would have needed more than 155T/H sustained over many hours in order to be successful, costing approximately $20M. On Proof of Work (PoW) blockchains, nodes achieve an objective network consensus by following one rule: the heaviest chain wins. Regardless of the node's hardware, location, and network connectivity; if they all follow that one rule, they will always reach consensus. MESS respects this rule, while enabling nodes to favor chain segments they see first over segments they see later. If the preferred chain is the first one the node sees (and is likely to be, since propagating blocks in public is the most profitable pattern for honest miners), building a long and potentially malicious chain in secret will no longer be viable. This innovative solution, an evolution of what Vitalik Buterin described as “Exponential Subjective Scoring,” back in 2014 on the Ethereum Foundation Blog, will ultimately increase network security while addressing a universal challenge for all PoW chains.
“MESS will enable exchanges to safely reduce confirmation times and ensure that miners will not lose block rewards; stabilizing the network and allowing it to return to growth,” said James Wo Founder and Chairman of ETC Labs.
About Ethereum Classic Labs (ETC Labs):
The mission of ETC Labs is to build relevant, accessible, and high-quality technology, and to use that technology to create communities of value in a mature and regulated ecosystem. The ultimate goal is to fulfill the promise of blockchain to improve people’s lives using Ethereum Classic, one of the world’s major public blockchains. The ETC Labs team of experts also fosters partnerships with organizations and institutions in order to address fundamental challenges in developing and deploying this innovative technology. We fulfill our mission in three ways: ETC Labs Accelerate, which invests in up to 25 blockchain projects annually that contribute to sustaining a robust ecosystem; strategic investments in innovative projects focused on economic and social development; and the ETC Core team of experts and developers who maintain the Ethereum Classic blockchain and build key applications, solutions, and tools. For more information, visit www.etclabs.org.