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Cryptocurrency in the 2020s

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Re: Cryptocurrency in the 2020s

#271

Post by nootropicat »

kerkeslager wrote: post #270
nootropicat wrote: post #259

Earlier quoted context omitted.

I assumed you meant manually. This method isn't possible to automate under PoW, because any such actions require global time, but PoW is what provides time itself, creating a contradiction. What this means in practice is network splits. >you know the transaction exists, and at some point (i.e. after a certain number of blocks), if the transaction isn't included in the chain, you can conclude with reasonable certainty…

EDIT: Everywhere I say that we wait 5 blocks/confirmations, that's just a number I picked. I think you could conservatively use fewer confirmations, but there's a bunch of network analysis you'd have to do to calculate what the probability of a transaction not being included in N sequential blocks simply due to network instability. I didn't do that network analysis, so you might need more or fewer confirmations to be…

Your solution regularly leads to orphans 5 blocks deep, making the network unstable. Now consider this:

- Chinese miners (the network doesn't know that) publish a normal transaction.

- they don't include it for 30 blocks. Western nodes have already switched to a minority uncensored chain after 5 blocks, as they consider the transaction censored.

- Chinese miners include it in 31st block.

A new node joins. It follows the Chinese chain indefinitely.

The core of the problem is lack of objective time (or at least ordering): there's no way to prove to the new node that a transaction was actually censored in the past. From its perspective, the minority chain might have been created after the Chinese block with the transaction was published. As long as there's no external objective time, it's always possible to invent some attack scenario that splits the network for new nodes.

Last but not least, every minority chain is by definition vulnerable to 51% attacks, so even if a solution to censorship could exist in PoW, the minority chain could get intentionally killed this way, constantly generating double spends until people stop using it.

Re: Cryptocurrency in the 2020s

#272

Post by l3kk0 »

asdfasgasdgasdg wrote: post #7

Consider the source, right? How many people without a large vested interest in the propagation and uptake of cryptocurrency consider further growth likely? My guess is that governments will more and more realize that the main utility of blockchains is money laundering and speculation. As has been remarked over and over again, they don't solve any above board problem more efficiently or with lower expense than existin…

Not true. Here's an example of how blockchain is changing real estate transactions and the title insurance industry:

https://www.deeds.com/articles/the-real-estate-deal-declutte...

This involves state and county governments recognizing a current problem that is easily solved with blockchain technology. In this particular use case, blockchain is used to prevent fraud and provide a more efficient process.

Re: Cryptocurrency in the 2020s

#273

Post by hnews_account_1 »

etrabroline wrote: post #261
dane-pgp wrote: post #245

Earlier quoted context omitted.

So you admit that increasing the block size by 10x would solve the current congestion/fees problem without needing the complexity and changed incentive structure of the Lightning network, and that bitcoin doesn't compete with Visa/Mastercard yet so it doesn't need a 30 TB blockchain (which would fit on two hard drives, which many consumers have). To give an analogy, it's like saying that there should be a law limitin…

>It doesn't matter what the size of the blockchain is now (as long as it's within say 1TB that the average consumer can access). Why does it have to fit on a laptop? Only miners influence which tx get into a block, not people on laptops. >The problem that won't exist of billions of transactions? Visa does 1 trillion tx/yr. Bitcoin tx is ~500 bytes That's just 500 TB/year. Miners with today's hardware can store that e…

People here keep harkening back to "but miners can handle that shit easily". It is entirely to avoid the setup where miners are the sole arbiters of the chain, that we require this. The entire point of bitcoin is to put power into the hands of people. Which means everyone needs to keep a copy of the blockchain instead of having a small number of entities with massive storage fighting against each other to decide which chain is valid.

The very fact that you guys are not recognising this means that you still don't understand the concept of decentralisation and want to settle with the altcoin route of making up the word as you go along and if it fits your narrative. If your entire chain was at the mercy of a few large mining corporations, you are dead in the water. The attack vector is easily compromised and you have no leg to stand on.

Re: Cryptocurrency in the 2020s

#274

Post by chii »

hnews_account_1 wrote: post #135
chii wrote: post #62

Earlier quoted context omitted.

whether crypto fans think or believe it to be false (or not care) is irrelevant. Crypto has only shown the characteristics of a speculative commodity (like gold), and the laws of economics are as universal as any other law - bitcoins cannot become a currency unless it is done by fiat (like how china is exploring doing so right now, but with their own version of a crypto-currency where they control the chain).

> the laws of economics are as universal as any other law No they are not. Can people please stop and think for a second before they vomit everything on their minds onto the keyboard and hit enter as fast as they possibly can in an attempt to make themselves heard in the noise? See what that looks like? Think about these things before you write them. Physical laws are immutable. If they not, they aren't a law. Econom…

> Economics is entire a human endeavour. The laws are what we want them to be.

no, that's just wishful thinking. Laws of economics are a description of human behaviour, and unless the human condition changes, it will always reflect self-interest and greed. Physical laws aren't "laws" in the same sense as human laws, but descriptions. Economic laws are the same; they describe what people would do under different incentivization schemes.

In this case, despite the proponents of crypto wanting it to be a currency, it has still languished as a commodity. This is due to the economics of using it, the interactions of it with the wider economy, and various other factors that i've termed under the umbrella of 'law of economics'.

Re: Cryptocurrency in the 2020s

#275

Post by kerkeslager »

nootropicat wrote: post #271
kerkeslager wrote: post #270

Earlier quoted context omitted.

EDIT: Everywhere I say that we wait 5 blocks/confirmations, that's just a number I picked. I think you could conservatively use fewer confirmations, but there's a bunch of network analysis you'd have to do to calculate what the probability of a transaction not being included in N sequential blocks simply due to network instability. I didn't do that network analysis, so you might need more or fewer confirmations to be…

Your solution regularly leads to orphans 5 blocks deep, making the network unstable. Now consider this: - Chinese miners (the network doesn't know that) publish a normal transaction. - they don't include it for 30 blocks. Western nodes have already switched to a minority uncensored chain after 5 blocks, as they consider the transaction censored. - Chinese miners include it in 31st block. A new node joins. It follows…

> Your solution regularly leads to orphans 5 blocks deep, making the network unstable.

Only if China decides to hamper the speed of their miners by pointlessly trying unsuccessfully to censor transactions.

> - Chinese miners (the network doesn't know that) publish a normal transaction.

> - they don't include it for 30 blocks. Western nodes have already switched to a minority uncensored chain after 5 blocks, as they consider the transaction censored.

> - Chinese miners include it in 31st block.

> A new node joins. It follows the Chinese chain indefinitely.

Okay, yes. And so does the entire rest of the network, because now the blocks are valid. Yes, this is very bad, because anyone who spent money in the shorter chain can now re-spend their coins.

But critically, nothing was censored here. This is a transaction reordering, not a censorship attack.

China can do the exact same thing with fewer steps. All they have to do is go back 30 blocks, and start mining blocks with the transactions in whatever order they want. Eventually their branch will be ahead and everyone will switch to it.

Re: Cryptocurrency in the 2020s

#276

Post by kerkeslager »

heptathorp wrote: post #255
kerkeslager wrote: post #249

Earlier quoted context omitted.

It delays finality, but it doesn't kill it. Reorgs are already possible, this is why we currently wait for some number of confirmations (6 last time I checked) to say a transaction is complete. Adding the condition of requiring all transactions you've received to be included in a chain means that you need to wait for more confirmations to reach the same level of confidence that the chain is final, but it doesn't mean…

Good points, thanks. Followup question: how does a node coming online know not to trust China's (longer, censoring) chain? It wasn't online to have the transaction in its mempool, so it doesn't know to check for it in the longest chain. I think it would need to check all candidate blocks with lower heights to see if their chains contain any transactions that aren't in a longer chain. What happens if I mine off of a v…

> Followup question: how does a node coming online know not to trust China's (longer, censoring) chain? It wasn't online to have the transaction in its mempool, so it doesn't know to check for it in the longest chain.

> I think it would need to check all candidate blocks with lower heights to see if their chains contain any transactions that aren't in a longer chain.

Yes. You wouldn't need to store all these, though, you just sweep them up once you find the transactions included in the longest chain.

> What happens if I mine off of a very old block and include my own transaction in it, and present it to you... how do you distinguish between what I just did vs the longer chain having censored the transaction this whole time?

Broadcast all transactions you have which aren't already in the longest chain to the network, and wait for them to include them.

I'm not 100% sure, but I think transactions get rebroadcast automatically already until they're included.

Re: Cryptocurrency in the 2020s

#277

Post by v64 »

nradov wrote: post #122
v64 wrote: post #16

Earlier quoted context omitted.

I honestly don't understand where the perception comes from that this technology is only useful for laundering and speculation. Certainly it is currently being used for those purposes. But to say there is no imaginable use outside of that seems unwarranted. I've commented in the past here that the use of public blockchains to automate the functions of clearinghouses and escrow services will be a huge cost reduction f…

Please explain exactly how blockchain technology can reduce costs for clearinghouses. Because they're already extremely efficient. There is very little transaction cost left to cut.

Ernst & Young have published some interesting data about the costs of private vs public blockchains, and how they've developed tools built on Ethereum to reduce those costs.

https://www.forbes.com/sites/benjessel/2020/01/06/ernst--you...

https://www.ey.com/Publication/vwLUAssets/ey-total-cost-of-o...

Re: Cryptocurrency in the 2020s

#278

Post by vehementi »

rolltiide wrote: post #40
vehementi wrote: post #25

Earlier quoted context omitted.

It is, but approximately 100% of startups (ICOs) formed around it have failed right? That's not to say there are none, but a fuck ton of people have tried to come up with cool ideas and approximately zero worked out, like at all.

Was the same in the second half of the 90s with tech/internet companies. Only in hindsight can you point to the 5 that didn't fail, but at the time you wouldn't have been able to pick them out from the lineup, or the graveyard, they probably weren't your favorites or you hadn't heard of them. Many programmers and sales people weren't able to get jobs and had to question their life choices. Its not so different with t…

Definitely not the same -- we're not talking about 2% of ICOs going on to become cool Google -- nothing of the sort is happening and it's been years. Moreover, despite the dot com bust, there were many legitimate companies that did have proven business strategies that weren't doing bubble stuff. People were using the internet to sell things, to advertise their sites, etc. and it was effective. Even that category of companies doesn't exist. Nobody's using bitcoin for any practical purpose... aside from dark market purchasing :)
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