Why was the chain with the largest work chosen as the metric of consensus?

1

There seems to be a myriad of ways to find consensus (PoW, PoS, PoD, PoE and various other methods and hybrid approaches).

What was the reasoning behind bitcoin being PoW and treating the chain with the largest amount of work as the correct chain? Is there something about PoW consensus that was inherently appealing to Satoshi or was it merely the default option?

Jack Fraser

Posted 2016-06-16T20:30:09.343

Reputation: 185

3The others didn't exist at the time, so how could Satoshi have compared them? This question is, essentially, does the Bitcoin whitepaper argue the case for PoW over any other (at the time hypothetical) consensus finding measures?4276 2016-06-16T20:53:42.130

@fredsbend Presumably satoshi had to invent PoW then as well. Is your objection that this question is too easy to answer or doesn't have an answer?Jack Fraser 2016-06-17T16:46:02.687

The question to me seems somewhat trivial. Unless I misunderstand what you are asking, it seems to say "Why did Satoshi decide on PoW?" Which comes with the assumption that he even spent mental effort thinking about anything else. Since we have a pretty limited library of Satoshi's writings (the whitepaper plus some forum posts) there's not much to investigate.4276 2016-06-17T16:53:41.143

Satoshi did not invent PoW. It was used in Hashcash several years before.Pieter Wuille 2016-06-17T17:03:38.920

Answers

2

At the time Bitcoin was invented PoS, PoD, PoE, did not yet exist.

Having said that PoW is arguably still the most secure today. The most popular PoW alternative today. PoS will always arguably be vulnerable due to the "Nothing at Stake" problem:

https://download.wpsoftware.net/bitcoin/pos.pdf

"The point is this: even if stakeholders are bonding coins with a large market value, in a way that they will lose the coins if they behave dishonestly, this is only a deterrent to dishonest behaviour until they move their coins, which, being an event in the future (both in realtime and blocktime), is necessarily not something that can be detected at the the current point in blocktime. So cheap histories, or “costless simulation”, are not something that can be prevented while only bonding value defined inside the system"

Hans Meyer

Posted 2016-06-16T20:30:09.343

Reputation: 283