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

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

#1
Hi folks! Can someone please tell me where my theory breaks? I theorize that 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. IE if you get enough people to say the sky is purple is the sky purple? Isn't cooperation key to a decentralized system? What happens when a new patch is released that pays you $100 to say a lie that user X has $0 and everyone involved has $100 more?

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

#2
You're forgetting that the integrity of the blockchain has value, particularly for miners. The token would crash once such a deception were made known making the miner's reward for mining worthless. That's the cost that you are not factoring into your example.

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

#3
There's a cost to run shards - bandwidth, processing and storage. Each transaction has a 2n1 cost (2 Parties, 1 shard, 'n' shards to sync too.) Decentralization has a high overhead to verify transactions over 'n' participants.

That why centralized ledgers were created. Sharded ledgers just means that you have smaller ledgers that have to be synchronized at some point. When you have more centralization you have larger chance of fraud.

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

#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.

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

#5
As another person said, that would damage the reputation of the network.

It reminded me of how in the movies a group of bad guys get away with the big briefcase of money and then two of them plan to get rid of the third guy and split the rest between themselves.

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

#6

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.

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

#7
Too many things going on here:

a. Are you aware of the Ethereum DAO hack? The whole Ethereum vs Ethereum classic. Short story - The largest ethereum contracts was hacked and money stolen. Then a patch was released saying that the hack didn't happen.

People who accepted the patch were "ethereum" holders and those who refused are now on "ethereum classic".

So, changing the rules in a patch doesn't matter. If there are enough people helping user x and the currency is still accepted it can be called 'currency classic/cash'.

b. There is a lot of confusion on whether cheating n blockchain somehow requires a patch or 51% support. It doesn't. 25% is enough to try and cheat within the rules. Read:

https://steemit.com/ethereum/@dhumphrey/update-f2pool-manipu...

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

#8
You're correct that cooperation is key and that if you get "enough" people (50% of hashing power in most cases) behind a plan, they can change the rules of the game. This could be used to steal coins.

This has actually happened in the past. When massive amounts of Ethereum were stolen from the DAO, the community got together and decided that those coins did not belong to the hacker. With >50% of the network, they forked the coin and created a refund contract where people could retrieve their stolen coins.[1] The dissenters remained to form what is now Ethereum Classic.

So, what prevents this from happening in a malicious way? The first hurdle is building that consensus. Many people involved in cryptocurrencies today believe that the future value is much higher than today's value. Paying them off would not be easy, especially considering that cashing out a large sum would crash the price of the coins, and thus the profits from your maneuver.

That being said, a core assumption of cryptocurrencies is that 50%+ of the network is not malicious. Another way of looking at this is that whoever controls greater than 50% of the network cannot be considered malicious from the network's perspective. They are they consensus.

The last point I'll make is speculative. If you created (or took over) a cryptocurrency and built consensus out of malicious actors, what value do you think the outside world would place on that coin? You would win lots of coins, but would anybody pay you dollars for them?

[1] https://www.cryptocompare.com/coins/guides/the-dao-the-hack-...

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

#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 that, it was up to the market to determine which version was more valuable. So far ETH is worth a lot more, so apparently the market was fine with this action in this particular case.

If people were to roll out a patch that committed a theft instead of repairing one, it's unlikely that many other people would go along with it. There'd be another split, the thieving chain would drop to a low value, and the original chain would keep rolling along with funds unstolen.

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

#10

You're correct that cooperation is key and that if you get "enough" people (50% of hashing power in most cases) behind a plan, they can change the rules of the game. This could be used to steal coins. This has actually happened in the past. When massive amounts of Ethereum were stolen from the DAO, the community got together and decided that those coins did not belong to the hacker. With >50% of the network, they for…

Now sell your coins...bitcoin is only worth something if it works. you'd also have to get bunch of people that have invested most of their lives to it.
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