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Can someone tell me where my decentralized/blockchain theory breaks?

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Re: Can someone tell me where my decentralized/blockchain theory breaks?

#21

Post by smokeyj »

tfha wrote: post #12

> the cost to get enough shared ledgers to agree that user x has 0$ (previously had $5M) is less than or equal to the amount of money that could be divided amongst the thieves That's the trick. In some cases, you'd be correct and the thieves can get away with theft. In most cases though you are incorrect, the cost of getting that many ledgers to agree with the thieves is prohibitively high. This theory underscores th…

> Large block supporters tend to think you only need a few full nodes to get immunity from these types of attacks

How exactly do you see an attack on full nodes going down? I imagine the attack would occur on the mining side..

Also, if the mempool becomes more expensive to host than blocks on disk - would you still think small blocks are safer?

Re: Can someone tell me where my decentralized/blockchain theory breaks?

#22

Post by valuearb »

golergka wrote: post #11

When you create counterfeit money, you damage people's trust in the money, which damages it's perceived value. You'd have to do it without doing catastrophic damage to the public trust, because then all you've stolen wouldn't have nay value. However, you could SHORT crypto currency and then do some damage it. Where would this logic break?

Shorting never damages anything, it's just a market adjustment mechanism.

Re: Can someone tell me where my decentralized/blockchain theory breaks?

#23

Post by EthanHeilman »

cantrip wrote: post #18
DennisP wrote: post #9

Something like this happened last year with Ethereum. A hacker stole $150 million, but the funds were conveniently trapped on one place for a month. People rolled out a patch that moved the funds back to their original owners. Some people thought that was a bad idea and kept running the unpatched version. That caused the blockchain to split into two separate blockchains, the patched (ETH) and unpatched (ETC). After t…

The term "hacker" depends on your viewpoint. Put another way, a user executed a function on a decentralized smart contract platform that transferred $150 million to the possession of the function's caller. If the value of smart contracts is that they will execute as written with no possibility of third party interference then Ethereum is not a smart contract platform. It is a very inefficiently designed public ledger…

>The term "hacker" depends on your viewpoint. Put another way, a user executed a function on a decentralized smart contract platform that transferred $150 million to the possession of the function's caller.

I think if you view the action as criminal or if you view it as just a clever use of the smart contract, the person who did this is a hacker. They understood and controlled the software in a way the designers did not intend.

Re: Can someone tell me where my decentralized/blockchain theory breaks?

#24

Post by borplk »

teolandon wrote: post #14
borplk wrote: post #6

Earlier quoted context omitted.

> 2. ledgers keep transaction histories, not absolute values. to clear someone's wallet, you have to transfer his money out. you can't forge that guy's crypto signature. As long as there's >50% consensus, they can do anything they want (longest chain wins). You don't need to forge someone's crypto signature to clear their wallet. You just stop agreeing that the guy has the 5m.

The longest valid chain wins. People can't add invalid blocks to the chain and have them be accepted by the rest of the community that is not in on it. The power of >50% is that you can keep some (valid) blocks on the chain, like some payments to a service provider, for as long as you want and have them accepted by the community because that's the longest chain that everyone's seen, and collect the service for that p…

Yes you are correct.

Re: Can someone tell me where my decentralized/blockchain theory breaks?

#25

Post by majormajor »

cantrip wrote: post #18
DennisP wrote: post #9

Something like this happened last year with Ethereum. A hacker stole $150 million, but the funds were conveniently trapped on one place for a month. People rolled out a patch that moved the funds back to their original owners. Some people thought that was a bad idea and kept running the unpatched version. That caused the blockchain to split into two separate blockchains, the patched (ETH) and unpatched (ETC). After t…

The term "hacker" depends on your viewpoint. Put another way, a user executed a function on a decentralized smart contract platform that transferred $150 million to the possession of the function's caller. If the value of smart contracts is that they will execute as written with no possibility of third party interference then Ethereum is not a smart contract platform. It is a very inefficiently designed public ledger…

> If the value of smart contracts is that they will execute as written with no possibility of third party interference then Ethereum is not a smart contract platform.

Why would there be such value in a dumb contract platform like that? Historically, what societies have chosen to adopt such a set of values?

Re: Can someone tell me where my decentralized/blockchain theory breaks?

#26

Post by ftlio »

smokeyj wrote: post #21
tfha wrote: post #12

> the cost to get enough shared ledgers to agree that user x has 0$ (previously had $5M) is less than or equal to the amount of money that could be divided amongst the thieves That's the trick. In some cases, you'd be correct and the thieves can get away with theft. In most cases though you are incorrect, the cost of getting that many ledgers to agree with the thieves is prohibitively high. This theory underscores th…

> Large block supporters tend to think you only need a few full nodes to get immunity from these types of attacks How exactly do you see an attack on full nodes going down? I imagine the attack would occur on the mining side.. Also, if the mempool becomes more expensive to host than blocks on disk - would you still think small blocks are safer?

The mempool is whatever you want it to be. You set the fee by which a transaction rides past your node.

And yes, multiple attacks have been attempted by the miner side on full nodes. The most recent being Segwit2X, which didn't get off the ground because convincing 100k nodes that their version of Bitcoin was different wasn't going to work.

Re: Can someone tell me where my decentralized/blockchain theory breaks?

#27

Post by billconan »

borplk wrote: post #6
billconan wrote: post #4

1. enough people means >50%, that's a lot. 2. ledgers keep transaction histories, not absolute values. to clear someone's wallet, you have to transfer his money out. you can't forge that guy's crypto signature. 3.whoever owns more than 5m would not probably put all the money under one wallet.

> 2. ledgers keep transaction histories, not absolute values. to clear someone's wallet, you have to transfer his money out. you can't forge that guy's crypto signature. As long as there's >50% consensus, they can do anything they want (longest chain wins). You don't need to forge someone's crypto signature to clear their wallet. You just stop agreeing that the guy has the 5m.

that guy has his 5m from a series transactions, you will need to drop the entire bitcoin transaction history to deny him do you?

You can censor him though I guess, ignore all his transactions.

Re: Can someone tell me where my decentralized/blockchain theory breaks?

#28

Post by borplk »

billconan wrote: post #27
borplk wrote: post #6

Earlier quoted context omitted.

> 2. ledgers keep transaction histories, not absolute values. to clear someone's wallet, you have to transfer his money out. you can't forge that guy's crypto signature. As long as there's >50% consensus, they can do anything they want (longest chain wins). You don't need to forge someone's crypto signature to clear their wallet. You just stop agreeing that the guy has the 5m.

that guy has his 5m from a series transactions, you will need to drop the entire bitcoin transaction history to deny him do you? You can censor him though I guess, ignore all his transactions.

Yes what I said is impractical.

Re: Can someone tell me where my decentralized/blockchain theory breaks?

#29

Post by DennisP »

cantrip wrote: post #18
DennisP wrote: post #9

Something like this happened last year with Ethereum. A hacker stole $150 million, but the funds were conveniently trapped on one place for a month. People rolled out a patch that moved the funds back to their original owners. Some people thought that was a bad idea and kept running the unpatched version. That caused the blockchain to split into two separate blockchains, the patched (ETH) and unpatched (ETC). After t…

The term "hacker" depends on your viewpoint. Put another way, a user executed a function on a decentralized smart contract platform that transferred $150 million to the possession of the function's caller. If the value of smart contracts is that they will execute as written with no possibility of third party interference then Ethereum is not a smart contract platform. It is a very inefficiently designed public ledger…

So obviously you're in the group which thought it was a bad idea to alter the ledger. I think there's a reasonable case to be made for that point of view. My point was that in the end, everybody got the chain they wanted.

I don't think the word "hacker" should be considered pejorative on a site called "Hacker News."

Re: Can someone tell me where my decentralized/blockchain theory breaks?

#30

Post by heptathorp »

cantrip wrote: post #18
DennisP wrote: post #9

Something like this happened last year with Ethereum. A hacker stole $150 million, but the funds were conveniently trapped on one place for a month. People rolled out a patch that moved the funds back to their original owners. Some people thought that was a bad idea and kept running the unpatched version. That caused the blockchain to split into two separate blockchains, the patched (ETH) and unpatched (ETC). After t…

The term "hacker" depends on your viewpoint. Put another way, a user executed a function on a decentralized smart contract platform that transferred $150 million to the possession of the function's caller. If the value of smart contracts is that they will execute as written with no possibility of third party interference then Ethereum is not a smart contract platform. It is a very inefficiently designed public ledger…

> It is a very inefficiently designed public ledger governed by a highly centralized group of developers who can change it on a whim.

But they can't just change it without the network going along with the change. And, after all, it is the network who decides what the code does in the first place by running the same protocol.

It's still a system governed by consensus. The network came to a consensus that it wasn't how the contract should have executed.

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