
Ask HN: Why was SAT-solving discarded as an Ethereum proof-of-work? - saurabh20n
In the pre-history of Ethereum, Vitalik talks of a SAT solving-based proof of work that was rejected. http:&#x2F;&#x2F;vitalik.ca&#x2F;general&#x2F;2017&#x2F;09&#x2F;14&#x2F;prehistory.html (5&#x2F;8th the way down)<p>Is there a public document related to this proposal? Better yet, its security analysis that led to it being discarded?
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zxcmx
Not involved in discussion but here is my take on it.

Most SAT instances are surprisingly easy to solve, hence the "unreasonable"
effectiveness of SAT solvers.

The construction of known-hard SAT instances is really building a new kind of
crypto primitive out of SAT, and TBH using this kind of primitive versus more
well known PoWs has little value to the network, is harder to analyse and is a
lot more work for developers.

I mean its useful from a research pov, you'd be building a money-based CTF for
solving certain theoretically hard types of SAT instances, but you are
basically sacrificing the stability (such as there is...) of the currency to
do so.

A really basic security analysis is "here is this thing which is pretty simple
to implement and we are very confident it works" versus "here is this new
thing that provides no extra intrinsic value, is more complicated, and we're
not sure about". I am not sure there was ever a "security proof" that it was a
bad idea because none was really required.

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saurabh20n
There are few comments here:
[https://www.reddit.com/r/ethereum/comments/2l0ht4/alternativ...](https://www.reddit.com/r/ethereum/comments/2l0ht4/alternative_proof_of_work_system_based_on_sat/),
but seems unlikely that was the entirety of the discussion.

