Earlier this month, researchers at the Hebrew University released a paper describing a mining method that would “obtain consistently higher mining rewards.” Is this an attack on Ethereum or the new standard of mining?
The paper, below, describes how F2Pool would change the timestamps of blocks in order to gain an edge on the competition.
The paper notes:
By carefully picking when to execute the attack, we can make sure that the attacker’s blocks will
have a higher difficulty when compared to the current tip of the blockchain, and thus will replace
it, but still will not have a higher difficulty compared to the block which the attacker would’ve
mined had it been following the honest protocol.Riskless Uncle Making
This screenshot shows us the algorithm that can be used to determine when to execute the timestamp change.
The quick version is, f2pool would change the timestamp of their blocks if the timestamp was divisible by 9. So if the normal timestamp was 9, they would lower it to 8. If it was 18, f2pool would lower to 17. So on and so forth. This gives their blocks a higher Total Difficulty, giving them an edge in the event of a tie.
And followed up with:
This reminded us a lot of ASICBoost with BitMain ASICs. At first, when only one or few knew about the method it was looked at as an unfair advantage.
Now, ASICBoost accounts for nearly 90% of all Bitcoin mining. It just became the standard method.
We consider this a new MEV and the new standard of mining. We have deployed patches to our nodes to deploy this Riskless Uncle Making mining method.
This is in the best interest of our miners, who choose ETC Pool for a reliable, optimized backend system. Having a low Uncle rate will increase the profit for our miners as well. This doesn’t mean we won’t ever have Uncle blocks. But we are dedicated to doing anything we can to optimize our pool.