Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Cryptocurrency Blockchains Don’t Need to Be Energy Intensive

spectrum.ieee.org

Post reply on HN
Print view View original

141–150 of 301 posts

Re: Cryptocurrency Blockchains Don’t Need to Be Energy Intensive

#141

Post by acjohnson55 »

dboreham wrote: post #128
aazaa wrote: post #107

> The granddaddy of all consensus mechanisms—behind Bitcoin, Litecoin, Monero, and (for the time being at least) Ethereum—is called proof of work. Essentially, PoW makes adding transactions to the blockchain computationally—and therefore financially—very expensive, so as to discourage fraudulent activity. ... This passage reflects a deep-seated, widespread misunderstanding of how/why Bitcoin works. I suspect the auth…

Another way to describe this is that PoW is a Cybil resistance measure.

Although just saying that doesn't really tell anyone much, who doesn't already know.

A Sybil attack is the creation of a bunch of identities to subvert a system that is attempting to distribute power amongst a bunch of participants.

The Sybil resistance of these schemes comes from allocating power in proportion to some form of commitment of a scarce resource, which could be indigenous to the system (e.g. proof of stake, proof of burn) or exogenous (e.g. proof of work, proof of storage).

I think it's noteworthy that all of these systems are plutocratic. They will all effectively redistribute wealth upward, because anything that doesn't would encourage the creation of more identities.

Re: Cryptocurrency Blockchains Don’t Need to Be Energy Intensive

#142

Post by fogof »

hypertele-Xii wrote: post #135
aazaa wrote: post #107

> The granddaddy of all consensus mechanisms—behind Bitcoin, Litecoin, Monero, and (for the time being at least) Ethereum—is called proof of work. Essentially, PoW makes adding transactions to the blockchain computationally—and therefore financially—very expensive, so as to discourage fraudulent activity. ... This passage reflects a deep-seated, widespread misunderstanding of how/why Bitcoin works. I suspect the auth…

I don't get it. Suppose a bad actor tries to double spend. They have to cryptographically sign both transactions, so the whole network will eventually receive knowledge of both transactions. Why can't the network simply wait for some duration of time before accepting a transaction, to verify that no double-spends propagate from elsewhere? If double spending is ever detected from a party, that party is dis-trusted by…

Well let's say we do things this way, and I double spend a transaction, sending one to Alice and one to Bob. Suppose Alice waits t seconds after receiving the transaction, and if she doesn't see any double spends in that time, she accepts that the coin is hers and she then sends me something in return.

One second before Alice "confirms" my transaction, I can send out my transaction to Bob. Since my message takes time to propagate through the network, it won't reach Alice soon enough and she will think I've paid her, and she'll send me whatever I was paying for. But other people will see both these transactions within t seconds of each other. They won't know which they should believe is correct, and they might not accept payment from Alice in the future.

Re: Cryptocurrency Blockchains Don’t Need to Be Energy Intensive

#143

Post by rytill »

fleddr wrote: post #93
Slartie wrote: post #70

Earlier quoted context omitted.

> nobody can just become richer because they started rich Right. In PoW, they need access to limited semiconductor supplies and cheap electricity. Which are two things that can be bought with...what was that stuff called...? Ah, yes: money! So PoW does just the same - the rich tend to get richer - but it adds the necessity to cause unnecessary environmental pollution on the scale of an entire country to it. Oh, and a…

No, they are far from the same. It's true that BTC mining is capital intensive, yet it is highly competitive and risky, and most miners get a decent profit, yet need to sell the vast majority of mined coins to run their operation. Miners can never move on some parabolic increase of wealth as the very protocol itself prevents this. Rather, we should look at holders. Bitcoin is fair in the sense that it does not have r…

That factor of “competitiveness” exists on Ethereum 2 as well. The more ether that is staked, the less the yield is from staking. If half of all ETH is staked, the APY will be below 2%, for instance. At a certain point bonds would overtake it.

Re: Cryptocurrency Blockchains Don’t Need to Be Energy Intensive

#144

Post by xwolfi »

aazaa wrote: post #107

> The granddaddy of all consensus mechanisms—behind Bitcoin, Litecoin, Monero, and (for the time being at least) Ethereum—is called proof of work. Essentially, PoW makes adding transactions to the blockchain computationally—and therefore financially—very expensive, so as to discourage fraudulent activity. ... This passage reflects a deep-seated, widespread misunderstanding of how/why Bitcoin works. I suspect the auth…

What I fail to understand, and thanks to your explanation, is why not use a central trusted ledger which would synchronize all transactions. It could surely work at the current speed of bitcoin and relieve the entire planet of the energy cost of bitcoin, providing the same safety that no double spend could happen.

All you'd need is a small private army, a few lawyers, an historically accepted jurisdiction, and you'd be ready to go with your central ledger.

I don't think you're right to say double spending is the only thing being solved with proof of work, I think people are trying very very very hard not to centralize (for no good reason in my opinion), despite the prohibitive cost, and why ? Because of that insane fear the ledgers would be changed: hence you'd have to admit the author was a bit right that eventually this whole story is to protect paranoid people against a very absurd risk at the cost of asking government to subsidize reopening coal mines...

Re: Cryptocurrency Blockchains Don’t Need to Be Energy Intensive

#145

Post by tromp »

CryptoPunk wrote: post #104
tromp wrote: post #61

Earlier quoted context omitted.

Of which the creators can grab an arbitrary part essentially for free.

They absolutely could not grab an arbitrary part for free. What an absurd claim. The BTC paid during the Ethereum crowdsale went to the Ethereum Foundation bitcoin address, and that address can be audited. Misappropriating those funds would leave a massive chain trail, and require a massive conspiracy to plant the Ethereum Foundation with co-conspirators. It would be unthinkable. On top of all of that, the operators…

> Misappropriating those funds

Where are the transparency reports detailing how the 31529 BTC raised in the crowdsale were spent?

It would seem straightforward to spend a large fraction of that on software development which would mean that the creators can take part in the crowdsale (which is largely anonymous) and have the spent BTC flow back to themselves.

Re: Cryptocurrency Blockchains Don’t Need to Be Energy Intensive

#146

Post by lisper »

fleddr wrote: post #125
viraptor wrote: post #113

Earlier quoted context omitted.

> If I'm rich and own 1,000 BTC whilst some poor slum has 0.001 BTC, neither of us has an advantage within the protocol. Why would we care about "advantage within the protocol" while ignoring the whole world around it? A similar absurd description is: one person is holding $1B in their hands, another is holding $1 - neither has more say about the money nor any advantage within the system as long as they don't spend i…

Because the protocol is software and only dictates rules inside its sphere of influence. It's a good rule that owning lots of coins does not automatically give you even more coins.

That rule does you no good if the net effect of the interplay of the rules with the rest of reality is that having more coins gives you more coins. This will be the case as long as coins can be used to purchase the means of production.

Re: Cryptocurrency Blockchains Don’t Need to Be Energy Intensive

#147

Post by DennisP »

hypertele-Xii wrote: post #135
aazaa wrote: post #107

> The granddaddy of all consensus mechanisms—behind Bitcoin, Litecoin, Monero, and (for the time being at least) Ethereum—is called proof of work. Essentially, PoW makes adding transactions to the blockchain computationally—and therefore financially—very expensive, so as to discourage fraudulent activity. ... This passage reflects a deep-seated, widespread misunderstanding of how/why Bitcoin works. I suspect the auth…

I don't get it. Suppose a bad actor tries to double spend. They have to cryptographically sign both transactions, so the whole network will eventually receive knowledge of both transactions. Why can't the network simply wait for some duration of time before accepting a transaction, to verify that no double-spends propagate from elsewhere? If double spending is ever detected from a party, that party is dis-trusted by…

That's similar to what Ethereum's proof-of-stake does. Any staker can submit the two inconsistent transactions as proof of malfeasance by another staker. When that happens, the misbehaving staker is automatically "slashed," losing a portion of their stake.

Re: Cryptocurrency Blockchains Don’t Need to Be Energy Intensive

#148

Post by rmtech »

hypertele-Xii wrote: post #135
aazaa wrote: post #107

> The granddaddy of all consensus mechanisms—behind Bitcoin, Litecoin, Monero, and (for the time being at least) Ethereum—is called proof of work. Essentially, PoW makes adding transactions to the blockchain computationally—and therefore financially—very expensive, so as to discourage fraudulent activity. ... This passage reflects a deep-seated, widespread misunderstanding of how/why Bitcoin works. I suspect the auth…

I don't get it. Suppose a bad actor tries to double spend. They have to cryptographically sign both transactions, so the whole network will eventually receive knowledge of both transactions. Why can't the network simply wait for some duration of time before accepting a transaction, to verify that no double-spends propagate from elsewhere? If double spending is ever detected from a party, that party is dis-trusted by…

The problem with waiting AFAIK is that it's vulnerable to attacks on the underlying peer-to-peer network.

Let's say you wait 1 hour to see whether there was a double spend. If an attacker wanted to, they could spend twice and somehow mess with the network for 1 hour.

For example, an attacker at the internet service provider could intercept packets from the Bitcoin network and just block the other spend transaction from getting to you. You wait 1 hour and consider the payment finalized, and you swap goods for Bitcoin.

Re: Cryptocurrency Blockchains Don’t Need to Be Energy Intensive

#150

Post by polynomial »

humperdink wrote: post #84
rawtxapp wrote: post #77

Earlier quoted context omitted.

A PoW miner has to spend to cover their costs, a staker doesn't have any cost to cover, providing a cryptographic signature requires no energy on an ongoing basis, just an initial investment. PoW requires constant investment or you'll be left behind.

I wish there would be more debate about the equity of a cryptocurrency amongst the tech community. Why should the least well off in society be part of a crypto-coin whose supply has been given to early adopters and insiders? Ultimately the social compact of the economy you create will involve everyone, so we should design a coin that solves hard problems, not just narrowly defined ones that conveniently benefit a nar…

> Why should the least well off in society be part of a crypto-coin whose supply has been given to early adopters and insiders?

Just taking a stab at it, maybe bc we haven't come up with a notion of how a viable crypto-coin could be started by the least well off, who are -by definition- at a competitive disadvantage in launching successful projects.

I'm not saying it's an impossible problem, just that these systems tend to be driven by economies of scale, whether it's new/disruptive, or the product of an older, more established regime.

And to be clear, I am not suggesting this with the finality of a foregone conclusion, but merely thinking aloud about the dynamic of the underlying problem.

Post reply on HN