The Ethereum (ETH) community has recently been engaged in a bitter debate sparked by a proposed mining algorithm change. Dubbed ProgPoW, the proposal would invalidate all currently existing ASICs to only allow mining Ethereum with a GPU.
While ProgPoW was born in 2018, it has seen alternate periods of stasis and active discussion during the two years of development. The latest round of debates was sparked by what, to some, seemed like a sudden reintroduction of ProgPoW into the Ethereum roadmap. During the Feb. 21 Dev call, Ethereum Improvement Proposal (EIP) 1057 — a formal ProgPoW specification — was marked as accepted and final.
Public dissent soon followed, eventually materializing into EIP 2538 on Feb. 25, which collected signatures from stakeholders opposed to the introduction of ProgPoW.
Cointelegraph tracked down Kristy Leigh-Minehan, one of the three original members of the IfDefElse group that created ProgPoW in 2018, to understand more about the algorithm and why it remains so divisive to this day. Cointelegraph also reached out to several Ethereum Foundation representatives, who declined to comment.
What is ProgPoW?
Shorthand for Programmatic Proof of Work, ProgPoW is a novel mining algorithm designed to be as resistant to ASIC — Application Specific Integrated Circuit — machines as possible. These devices are specifically designed for the task of mining, which makes them much more efficient than consumer options such as CPUs and GPUs.
Making an algorithm that remains secure against optimized hardware has been traditionally a difficult task. The current algorithm used by Ethereum — Ethash — has also been designed for ASIC resistance, but its protection did not last for long. As Minehan recounted, rumors of an Ethereum ASIC were the initial motivation for her group’s work:
“ProgPoW was born out of the ASIC resistance threads in March 2018. An Ethereum contributor called Pipermerriam posted EIP 958, which was an EIP to modify the mining algorithm of Ethereum to be ASIC resistant. This was triggered by the discovery of the E3 ASIC miner by Bitmain, which had been leaked on CNBC.”
And even though it was later understood that the E3 was a crude device, with Minehan describing it as “a bunch of DDR 3 memory connected to their [Bitmain’s] Sophon chips,” the ball on ASIC resistance got rolling. Proponents of ProgPoW argue that it’s harder to manufacture specialized Ethereum ASICs, which will lead to fewer miners and subsequent centralization.
A poll by Vlad Zamfir, researcher at Ethereum Foundation (EF), concluded in April 2018 with 57% of votes in favor of a hard fork preserving ASIC resistance. Around the same time, EIP 969 proposed to make a small change in Ethash to break existing ASICs. Minehan continued:
“Those two EIPs, plus the constant discussion around ASIC resistance was what really spurred us — as IfDefElse — to start looking more into how would you go build a truly ASIC resistant algorithm.”
From a high level technical perspective, Minehan explained that ProgPoW works by tweaking Ethash to utilize 100% of a GPU chip. This was because ASIC manufacturers generally try to remove as many parts of it as possible, as she elaborated:
“The reason we do that is because currently when you go to build an ASIC, what you do is you strip away portions of a GPU. You basically say: ‘hey, here's the reference code, here's the GPU — which parts can we take away from the chip?’”
Ethash attempted to defend from this by trying to utilize the GPU as much as possible, which is why some of ProgPoW’s technical changes are small, but crucial alterations to Ethash that fix some of its inefficiencies and vulnerabilities. “I just think that whoever designed it [Ethash] wasn't a GPU programmer, so he missed some basic things,” she added. Read More...