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booppoob

Please provide sources and/or elaboration for/on the following:

* Deliberate slowness.

* Comparative slowness (given the problem space).

* 1/3 collusion breaking trust-less consensus.

* A definition of "us", "trust" and "scale" for your 6th line.

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The PoW blockchain is slow to propagate updates but design. If you don't know how proof of work blockchains work, I advice you to Google around for a nice technical breakdown. Suffice to say, it is fundamental and a property people specifically code in to make blocks take a specific amount of time to complete.

As for the 1/3 citation, I guess that's slightly less known: "Selfish Mining". Citation: https://arxiv.org/pdf/1311.0243

Of course "1/3" is a joke. It's actually closer to 1/4.

TL;DR for those of us on small viewports?

People can collude to get a disrporotionate amount of the profit from a blockchain. The more people collude, the more profit they get, the more rational it is to join them.

This then bridges into traditional 51% attacks.

> The more people collude, the more profit they get, the more rational it is to join them.

This is not true. Colluders diminish the value of their PoW reward by reducing the trust of all other participants in the system and honest actors have an even strong incentive not to join them. Just a few years ago a mining pool that gained a very large share of the Bitcoin hashrate had members choose to leave -- https://www.coindesk.com/bitcoin-miners-ditch-ghash-io-pool-...

Please see the referenced paper. They address this.

Because Selfish Mining attacks are not inherently detectable, you cannot expect the average user to detect them.

Too many refutations of selfish mining appeal to an oracle. This is an example of such an argument.

If the big miners need to self regulate like that, then why bother with proof of work in the first place?

You say, "traditional," but has one ever actually taken place?

Bitcoins are mined by a uniformly random process, which means even groups with a small amount of power can mine blocks, and even can occasionally mine more than one in a row. But instead of publishing that mined block immediately, there is a better strategy. Waiting on publishing makes a fork, and the colluders can keep mining on the fork until the strategy defines that they should publish - which is basically when the "honest" branch catches up to the colluding branch. Since the colluders don't have a majority, this will always happen, but that's ok.

Due to the way that the Bitcoin protocol works, honest miners will sometimes "help out" the colluding group by mining on that published fork. This basically amplifies the power of the colluding group, which is the goal. Worse, the paper proposes that the percentage of honest miners switching to the fork can be influenced cheaply, by choosing which blocks to forward along in the p2p network.

Interesting. Wouldn't this be riskier than non-collusion, since it diverts hashpower from the main chain and the merging of the side chain depends on help from non-colluding miners?

Great paper!

> Deliberate slowness.

As OP article alludes, bitcoin difficulty is tuned for a very long interval between blocks, to reduce the risk of nearly-simultaneous "uncle" blocks.

Other blockchains such as Ethereum have seemingly successful alternative approaches. IMO the article has a very limited perspective on blockchain technology. It's understandable, since the space is exploding and very hard to keep a handle on, but I think it should be less sweeping in its claims.

That doesn't really solve the problem at all though.

Ethereum beautifully solved the problem of "how do I cheaply make a token with trustless trading semantics?", and it's been used to raise billions of dollars of funding. So that might depend on the problem you're talking about.

There's an enormous amount of interesting blockchain technology, so sweeping dismissals of it tend to be lazy and ignorant.

> to raise billions of dollars of funding

How much of that was neither exit scammed nor lost to contract bugs?

Not the point. It's obviously introduced new problems, but does provide a highly valued capability. Sweeping dismissals of the space based on bitcoin's design are ignorant and lazy.

How do we know there isn't a selfish mining ring owning and subtly biasing Ethereum?

I want a good answer to this question before I put money back in. Because tbqf, it's very easy to raise capital on buzzwords. Especially if you're so we'll suited to money laundering.

It should be possible to check for autocorrelation of block arrival times, and correlation with forks. I don't know whether anyone's gone looking for that, but Eyal and Sirer have a strong incentive to monitor for it, and obviously have the chops to do so.

While there are bad actors in every system, how that system handles bad actors is still relevant and to the point when judging it.

Hardly lazy. The entire space has existed for 10 years and the underlying tech for even more. So far all that has been produced is massive amounts of fraud. If you want to count pump and dump scams, Ponzi schemes, pyramid schemes, terrorist funding, organized crime money laundering schemes, crypto-locker scams, “underage kids buying hardcore drugs” schemes, child trafficking schemes, blatant tax fraud, “hiding money from the ex wife” schemes, and all the other underground frauds, scams and criminal behavior as “valuable”, be my guest.

... oh and all at the low low cost of the several small nations worth of electricity required to power the brutally slow, inefficient by design Rube Goldberg contraption that is the blockchain...

The whole space is a joke.

how much of the internet was dedicated to porn and funny pictures?

Over 99% of it?

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