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Proof of stake is incapable of producing a consensus

yanmaani.github.io

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Re: Proof of stake is incapable of producing a consensus

#771

Post by dorgo »

akrymski wrote: post #752
darawk wrote: post #687

Earlier quoted context omitted.

Except that they are though...You can go run a validator on Eth or Cardano right now.

Sure, but if the majority of validators are actually run by the project owners it's effectively centralised. And it's easy to maintain this control if you have the majority of coins to stake. It's not Sybil resistant for this reason - all validators could be owned by one person and you would have no way of knowing.

>all validators could be owned by one person and you would have no way of knowing.

all bitcoin miners could be owned by one person and you would have no way of knowing....

>it's effectively centralised

so your argument is not that it is not possible to have security AND decentralisation with POS, but that it currently is not the case, right?

Re: Proof of stake is incapable of producing a consensus

#772

Post by javert »

iostream23 wrote: post #763
javert wrote: post #668

Earlier quoted context omitted.

I agree with this. Just want to add, bitcoin mining can happen in remote locations with available power (hydro, geothermal) which are too far from cities to be transported by power wires. There is a limit to how far you can transmit electricity through wires. So, there are tons of untapped natural energy sources.

And precisely in places like these, such as Niagara Falls, you see coin mining displacing tangible goods production due to both needing cheap electricity and one being more profitable than the other. In this case the market is not thinking very clearly in long term priorities, nor is infinite development of hydro and geothermal possible. Actually, this is about realizing that we live on a finite planet with finite re…

You're ignoring the potential good of bitcoin there. All economic activity looks like a waste if you ignore what it's good for.

Niagara Falls is not what I had in mind. There is lots of untapped hydro power in extremely remote parts Canada where nobody lives, for example.

Re: Proof of stake is incapable of producing a consensus

#773

Post by DennisP »

yanmaani wrote: post #761
DennisP wrote: post #704

Earlier quoted context omitted.

PoS is a class of consensus protocol, not any particular blockchain. It's orthogonal to signature algorithms. A blockchain can incorporate any combination of consensus algorithm and signature algorithm. So yes, please use your terms correctly. If sufficiently powerful quantum computers become readily available to anyone, sure, everybody will upgrade. Given the exotic hardware they typically require, it seems likely t…

If you're fine with changing algorithms, wouldn't PoW also be able to change to something more quantum-resistant?

Grover's algorithm is pretty general, I don't think there is anything we know about that we could switch to.

Shor's is faster but more specific. It works on factoring and elliptic curves, but not on hashes. The advantage of Shor's is that if you have enough qubits, you can get the answer immediately. Grover's only offers quadratic speedup, effectively halving the number of bits in the hash function.

So for signatures we just need to switch to something like a hash-based signature algorithm, with keys having twice as many bits as we'd want against classical attackers. But we don't have hash functions that keep Grover's from working, so a quantum miner be way faster than classical miners.

Re: Proof of stake is incapable of producing a consensus

#774

Post by EthanHeilman »

xorcist wrote: post #710
EthanHeilman wrote: post #628

Earlier quoted context omitted.

A trust assumption of PoS (Proof of Stake) is that >66% of the stake is honest. If you violate this trust assumption then yes PoS breaks. This is a similar trust assumption to requiring that 51% of the mining power in PoW (Proof of Work) is not malicious. This risk can be mitigated: 1. The network should halt if a fork is detected. A fork with more than 66% of the stake behaving maliciously means a fundamental trust…

> Stop everything! Let humans figure out what is going on. What does this mean in practice? Who are these humans? When can the network get going again? Would a consensus rule change be part of it, and what type of changes would be allowed in that situation? It sounds hard to manage this type of maintenance breaks in a trustless way. Surely consensus rule changes during outages should not be handled any differently th…

> What does this mean in practice? Who are these humans? When can the network get going again? Would a consensus rule change be part of it, and what type of changes would be allowed in that situation?

We have a bunch of examples of this happening in practice. The humans are usually a mix of the developers, parties important to consensus (miners, stakers) and big ecosystem players.

> It sounds hard to manage this type of maintenance breaks in a trustless way.

When solving a problem that violates your core security assumption you are only longer in the world of security definitions. It doesn't really make sense to talk about "trustlessness". If the protocol is busted, you need to find a solution and get enough people on board with that solution that you can upgrade the protocol.

> Once you have established the trust required for checkpointing the entire blockchain regularly, wouldn't it be much easier to checkpoint every block instead and in an instant do away with all the hard problems of blockchain networks?

The checkpoints aren't trusted for safety but instead for availability. Instead you should think of them like alarms that "something has gone horribly horribly wrong, stop everything, don't transact, don't move, don't touch anything, pull the ebrake."

tl;dr Much like the fuse box in your house, my view is that checkpoints should turn safety failures (electrical fires) into availability failures (electricity is shut off).

Re: Proof of stake is incapable of producing a consensus

#775

Post by javert »

iostream23 wrote: post #762
rufusroflpunch wrote: post #658

Earlier quoted context omitted.

I wouldn’t worry about it. Bitcoin incentivizes energy development. As the world moves to a Bitcoin standard, we will unlock new types of energy that were previously unproductive. It’s likely that energy will more cheap and plentiful under a Bitcoin standard, leading to downward pressure on transaction prices as mining is more economical. Also, more transactions are likely to move off chain to Lightning Network and s…

Bitcoin proof-of-work difficulty must always increase, the electrical needs are always ever-growing. While you claim that incentivizing electrical production is what POW does, in reality it is a large drain of electricity on a finite electrical grids capacity and it DOES take away from other uses of electricity LIKE aluminum smelting or running hospitals. It is an active and actual source of pollution and uses more e…

Bitcoin difficulty does not always increase and needs not always increase.

As for the rest... so what? It uses a lot of electricity and there is some pollution---but a lot of bitcoin mining is done with hydro or geothermal (and will be nuclear if bitcoin continues to grow), so, so what about some pollution?

Re: Proof of stake is incapable of producing a consensus

#776

Post by cutemonster »

ogogmad wrote: post #459
lottin wrote: post #340

Earlier quoted context omitted.

Yes, I read it. As far as I can see, it talks about 'staking', so it doesn't address what happens when the tokens and 'expended' as opposed to 'staked'.

You have two competing chains: Chain 1 and chain 2. On chain 1, you spend a token on a good. On chain 2, you spend no token. You wait for chain 1 to win the race. You then stake on chain 2 to get your money back. If chain 2 then overtakes chain 1, you've executed a double-spend attack. An equivalent attack wouldn't work on a PoW chain. If you do the equivalent of "staking" on chain 2, then you're computing hashes, wh…

Thanks for explaining (I'm a different someone)

There was a PoS mechanism that makes people who cheat lose all their coins? I wonder if it is relevant here

... Aha, that's "slashing" -- the other members in the network would look at the two chains, and notice that you were misbehaving, and add transactions that remove parts of your coins? (They'd add to both chains? Or just the winning one?)

Re: Proof of stake is incapable of producing a consensus

#777

Post by drdeca »

larsrc wrote: post #196
Zpalmtree wrote: post #180

Earlier quoted context omitted.

Such an idiotic proposal. How should we enforce this, do we need a government backdoor on every single turing complete hardware to verify they are not running """bad"" code (hashing data)? Or are just ASICs the problem, mining with CPUs is OK? Or maybe you could just let people do what they like with the electricity they paid for

If electricity was an unlimited non-polluting resource, sure. But when my neighborhood mining rig coal power plant gives me cancer, it's not just a simple marketplace thing.

then tax the electricity use (or, specifically, the fossil fuel use)?

(alternatively, tax the electricity use beyond a certain per-person allocation).

I agree that there can be harms from PoW, but this is because of the electricity use, and so the thing to tax is the electricity use. Rather than the state deciding what things it considers valid for an individual to value and seek, it should put the restrictions on the thing that more directly causes negative externalities to others.

If there is a concern that this would harm things that we are sufficiently convinced is objectively valuable (e.g. making it more costly than is appropriate for people to heat their homes), so that we want to not significantly impact the finances of people who are like, using "reasonable" amounts of electricity, then we can, as I said, put some threshold amount of electricity use per person below which there's no tax on it, and increase the tax rate above that amount to account for this (and use the revenue to pay for CO2 removal and/or green energy development).

Or, like, I suppose in the most extreme case you could (on e.g. an annual basis) give everyone an initial amount of CO2 credits and no one is allowed to emit CO2 beyond the credits they have (but unused credits can be bought and sold).

Re: Proof of stake is incapable of producing a consensus

#778

Post by pmorici »

rank0 wrote: post #46
pmorici wrote: post #41

Earlier quoted context omitted.

“Decentralization” has been the argument ideologues have fallen back on time and again in crypto. It’s never well defined and typically used to oppose policies that would promote low transaction fees or increased transaction throughput. It’s why things like Solana which is focused on massive scale and low fees have found a foothold. Ethereum is repeating the mistakes of Bitcoin

It’s because if you’re not decentralized, then you don’t need a blockchain.

The issue is what constitutes a sufficient amount of "decentralization". Extremists who may or may not have ulterior motives seem to oppose any change which by their estimation might decrease the decentralization. They want to minimize the cost of running a full node without consideration for the fact that optimizing that to the extreme causes transaction fees to go parabolic and thus also prices less well off users out of participating in the network and if the fees are too expensive to transact why would you run a full node for a network you can't use. There is no balance in their thinking.

Re: Proof of stake is incapable of producing a consensus

#779

Post by drdeca »

iostream23 wrote: post #762
rufusroflpunch wrote: post #658

Earlier quoted context omitted.

I wouldn’t worry about it. Bitcoin incentivizes energy development. As the world moves to a Bitcoin standard, we will unlock new types of energy that were previously unproductive. It’s likely that energy will more cheap and plentiful under a Bitcoin standard, leading to downward pressure on transaction prices as mining is more economical. Also, more transactions are likely to move off chain to Lightning Network and s…

Bitcoin proof-of-work difficulty must always increase, the electrical needs are always ever-growing. While you claim that incentivizing electrical production is what POW does, in reality it is a large drain of electricity on a finite electrical grids capacity and it DOES take away from other uses of electricity LIKE aluminum smelting or running hospitals. It is an active and actual source of pollution and uses more e…

The difficulty does and has (in the short term) decreased when the amount of hashpower being used goes down.

Presumably if the price went down by a substantial chunk and stayed down for a while, the hashpower would also decrease, and so the difficulty would also decrease.

Also, if electricity prices went up, or if CO2 emissions were taxed, then hashpower would decrease, and the difficulty would go down in turn.

Re: Proof of stake is incapable of producing a consensus

#780

Post by drdeca »

inter_netuser wrote: post #365
lottin wrote: post #327

Earlier quoted context omitted.

Nodes have zero decision power, as far as I understand. They just go with the chain that is the most expensive to produce.

That’s incorrect. The proposed block must comply with the rules your node enforced, or it will not be accepted. It’s not just work, but also the entire consensus-set they must abide by. Miners cannot force new rules, if there is no consensus.

Eh? Can't miners refuse to include transactions that don't adhere to new conditions in addition to old ones?

If 51% of miners decide to, after block #N, not include any transaction that doesn't satisfy the predicate P in any block they produce, nor mine on any chain which has a block after block #N which has a transaction that doesn't satisfy predicate P, then the longest chain will have all the transactions after block #N be ones which satisfy P, and furthermore, if the other 49% of miners are aware that this is happening, if they want their blocks to be in the longest chain, they have incentive to follow the same rules when mining.

This is the logic behind soft forks, is it not?

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