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> The established value of the consensus is the transactions contained within the block. Which of them? Because every node has a slightly different view and do

by dozzie 9y ago

> The established value of the consensus is the transactions contained within the block. Which of them? Because every node has a slightly different view and doesn't know how it differs from anybody else's view. > That's the point, one should not have to consider the values of other nodes to reach consensus. If the network agrees on something, that's consensus. If a certain node doesn't, that's their problem. The problem is that every node has slightly different view. You can't tell "this is the agreed value", because no particular node has this value as its state. Yet somehow it emerges as network's agreed value? By what means (algorithm) anybody can take a list of transactions and say "this is the network's agreed value"? Not to mention that the list of transactions constantly changes, you didn't address the problem that agreed value requires the protocol to terminate first. > It's agreed because that miner solved the block problem first. If you have a different view, you must fix it. This is how it achieves consensus. In what way is "solve block problem" consensus? > Not sure what specific consensus problem Nakamoto consensus doesn't solve, Yes, this is typical problem with blockchain enthusiasts. They're usually too uneducated and don't know the fundamentals, like the definition of consensus problem. I pointed you to Byzantine generals paper already, it should have been easy to find even with just "consensus problem Lamport" keywords.

zero-x 9y ago
Just because it doesn't fit into your contrarian view on consensus it doesn't mean it doesn't provide consensus. Nakamoto consensus solves the Byzantine problem quite well. The list of transactions doesn't not constantly change? Are you saying there is no consensus as to the value of the first blocks? I get that it's cool to be contrarian and it makes people feel smart to badmouth blockchain. But Nakamoto consensus does reach a consensus on value that is accepted by the network. It's like saying a voting election didn't matter because certain people didn't participate.
- dozzie 9y ago
  > Just because it doesn't fit into your contrarian view on consensus it doesn't mean it doesn't provide consensus. You do realize that this "my contrarian view" is what computer science calls "the consensus problem", right? And that "my contrarian view" comes from a highly regarded publication that's thirty years old? > Nakamoto consensus solves the Byzantine problem quite well. Explain to me how. Byzantine generals problem comes with a rigorous proof that network cannot agree on a single value if the cooperating nodes don't outnumber the adversarial ones by more than 2:1. The blockchain guarantees its functions with merely 50% + 1 of cooperating nodes. Something doesn't add up if blockchain was intended to solve consensus problem. > I get that it's cool to be contrarian and it makes people feel smart to badmouth blockchain. Oh, but I don't badmouth blockchain. I think it's quite ingenious cryptosystem. I only badmouth blockchain enthusiasts, and the undereducated ones at that. Blockchain was never intended to be a consensus protocol, it was always a timestamping protocol. We had a number of those before, but blockchain is the first one that doesn't use trusted third party. This is the ingenuity of blockchain, not consensus that blockchain doesn't solve. And then the idea behing Bitcoin, that a digital cash protocol (of which we had some number before, too) can be built on top of published and timestamped transactions, which together form a ledger. This is smart as well. But it's still not a consensus protocol. > But Nakamoto consensus does reach a consensus on value that is accepted by the network. Despite that nobody can tell what value exactly was agreed upon? And despite that you can't designate any specific point in time that the agreement is reached? I fail to see how is this "consensus".
  - zero-x 9y ago
    It's quite simple really. Do all miners [eventually] agree on the value of a block? Yes? That's a consensus. True there are other types of consensus that are perhaps 'fairer' but that's not the issue here. So yes, it is a consensus protocol. It's called Nakamoto consensus, and it's perfectly fine for its purpose.
    - dozzie 9y ago
      > Do all miners [eventually] agree on the value of a block? Yes? That's a consensus. It's amazing how many things you got wrong in such a short statement. First, a program can't say when this "eventually" is. Then the "agree" part is wrong, too, because it can change just like that (because of forks), which even changes the history, not just a single transaction or group of them. And then there's also "all miners" part, which even read as customary universal quantifier ("all" meaning "most of them") falls apart if you remember that this needs to be assessed by a program with limited knowledge. It's not a consensus in any computer related meaning that one could think of.
      - zero-x 9y ago
        This is just silly. By these arguments even block #1 has no consensus and has not terminated. Because "it might fork" that's why it's not a consensus? lol, ok buddy.
        dozzie 9y ago
        Dude, you haven't provided any usable criteria to declare any particular block as "agreed upon". All you said was "eventually", and even that has flaws. It's not something to argue against well known mathematics.
        YuriNiyazov 9y ago
        Don't argue with us. Argue with satoshi. https://www.mail-archive.com/cryptography@metzdowd.com/msg09997.html https://www.mail-archive.com/cryptography@metzdowd.com/msg09...

by dozzie 9y ago

zero-x 9y ago

Just because it doesn't fit into your contrarian view on consensus it doesn't mean it doesn't provide consensus. Nakamoto consensus solves the Byzantine problem quite well. The list of transactions doesn't not constantly change? Are you saying there is no consensus as to the value of the first blocks? I get that it's cool to be contrarian and it makes people feel smart to badmouth blockchain. But Nakamoto consensus does reach a consensus on value that is accepted by the network. It's like saying a voting election didn't matter because certain people didn't participate.

dozzie 9y ago
> Just because it doesn't fit into your contrarian view on consensus it doesn't mean it doesn't provide consensus. You do realize that this "my contrarian view" is what computer science calls "the consensus problem", right? And that "my contrarian view" comes from a highly regarded publication that's thirty years old? > Nakamoto consensus solves the Byzantine problem quite well. Explain to me how. Byzantine generals problem comes with a rigorous proof that network cannot agree on a single value if the cooperating nodes don't outnumber the adversarial ones by more than 2:1. The blockchain guarantees its functions with merely 50% + 1 of cooperating nodes. Something doesn't add up if blockchain was intended to solve consensus problem. > I get that it's cool to be contrarian and it makes people feel smart to badmouth blockchain. Oh, but I don't badmouth blockchain. I think it's quite ingenious cryptosystem. I only badmouth blockchain enthusiasts, and the undereducated ones at that. Blockchain was never intended to be a consensus protocol, it was always a timestamping protocol. We had a number of those before, but blockchain is the first one that doesn't use trusted third party. This is the ingenuity of blockchain, not consensus that blockchain doesn't solve. And then the idea behing Bitcoin, that a digital cash protocol (of which we had some number before, too) can be built on top of published and timestamped transactions, which together form a ledger. This is smart as well. But it's still not a consensus protocol. > But Nakamoto consensus does reach a consensus on value that is accepted by the network. Despite that nobody can tell what value exactly was agreed upon? And despite that you can't designate any specific point in time that the agreement is reached? I fail to see how is this "consensus".
- zero-x 9y ago
  It's quite simple really. Do all miners [eventually] agree on the value of a block? Yes? That's a consensus. True there are other types of consensus that are perhaps 'fairer' but that's not the issue here. So yes, it is a consensus protocol. It's called Nakamoto consensus, and it's perfectly fine for its purpose.
  - dozzie 9y ago
    > Do all miners [eventually] agree on the value of a block? Yes? That's a consensus. It's amazing how many things you got wrong in such a short statement. First, a program can't say when this "eventually" is. Then the "agree" part is wrong, too, because it can change just like that (because of forks), which even changes the history, not just a single transaction or group of them. And then there's also "all miners" part, which even read as customary universal quantifier ("all" meaning "most of them") falls apart if you remember that this needs to be assessed by a program with limited knowledge. It's not a consensus in any computer related meaning that one could think of.
    - zero-x 9y ago
      This is just silly. By these arguments even block #1 has no consensus and has not terminated. Because "it might fork" that's why it's not a consensus? lol, ok buddy.
      - dozzie 9y ago
        Dude, you haven't provided any usable criteria to declare any particular block as "agreed upon". All you said was "eventually", and even that has flaws. It's not something to argue against well known mathematics.
        YuriNiyazov 9y ago
        Don't argue with us. Argue with satoshi. https://www.mail-archive.com/cryptography@metzdowd.com/msg09997.html https://www.mail-archive.com/cryptography@metzdowd.com/msg09...