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The bitcoin consensus mechanism is literally a lottery in which the winner gets to decide what the "consensus" is. I don't know about "revolutionary"...

by lottin 5y ago

rantwasp 5y ago
is it though? the “lottery winner” in your case assembles a block with transactions from the transaction pool (ie you don’t just make shit up. you are taking useful transaction that people are making them and capturing them into the chain) So the winner does not decide much, except maybe what transactions to select (spoiler alert: the transactions with the highest fees are normally selected). The consensus is in the sense that: you wanted to create a transaction and that transaction is captured and everyone in the network sees and agrees that the transact happened. The miner cannot alter your transaction. Other nodes in the network cannot arbitrarily reject it. You cannot simply claim you didn’t do it after the fact.
- lottin 5y ago
  > everyone in the network sees and agrees that the transact happened Why would everyone agree that the transaction happened?
  - rantwasp 5y ago
    everyone == bitcoin nodes that each keep a copy of blockchain locally. once a block is mined it is propagated through the network and it’s verified by all the nodes that see it. In effect, when you get the block and you append it to your local blockchain after verification you agree that the transaction that happened in that block happened.
    - lottin 5y ago
      Yes, but the question is why would all the nodes agree that the transaction has happened. What's stopping them from disagreeing?
      - Arnavion 5y ago
        They're welcome to disagree. I can write a node that creates a chain with blocks that only contain some transactions of my choice and then broadcasts it. For nodes that only have access to my chain, they will also go with my chain. This is why being connected to multiple nodes is important. For nodes that have access to both my chain and the rest of the world's chain, they will go with the chain that has the most work put into it, because that is the one that is clearly supported by the majority computation power. It's irrational to go with the chain that has less power, because the entities that created the chain with more power can easily overwrite the chain with less power by virtue of having more power. Unless I happen to have more computation power than the rest of the world, the chain with more work put into it isn't going to be mine, which is why it's important that global computation power isn't consolidated into a single miner.
        rantwasp 5y ago
        hmm. it’s not necessary more power. Sometimes it’s luck if you are talking about chains that are the same except the tip where they differ by 1-2 blocks.
        lottin 5y ago
        > It's irrational to go with the chain that has less power, because the entities that created the chain with more power can easily overwrite the chain with less power by virtue of having more power. This basically means the entire bitcoin network depends on the entities that have the most computer power behaving correctly, am I wrong?
        Arnavion 5y ago
        That is correct. As I wrote in [1], the situation where the majority power becomes irrational is a doomsday scenario for bitcoin. [1]: https://news.ycombinator.com/item?id=28020592 https://news.ycombinator.com/item?id=28020592
        lottin 5y ago
FabHK 5y ago
> The bitcoin consensus mechanism is literally a lottery It is, but with the probability of winning proportional to the "work" you put in. That is crucial.
- lottin 5y ago
  Just like any lottery. The more tickets you buy the higher the probability of winning a lottery. In the bitcoin lottery the tickets are cpu power.
  - rantwasp 5y ago
    not a lottery. in case of a lottery, when you have the winning numbers you go to a central authority that manages the whole thing and you claim the winnings. Also, in case of a lottery the winnings are a share of what has been put into buying the tickets. also, lotteries can go a long time without having a winner for the jackpot. Also for lotteries, usually there is a tiered winning structure and what you win on is fixed (ie the numbers) for bitcoin there is no central authority. the reward for winning is “fixed” and claiming the said reward is dependent on a network that validates that you indeed have the work that incorporates pending transactions into the blockchain. also, “winning” happens at regular intervals of time (average 10 minutes based on difficulty), and what you’re winning is somewhat fixed (the block reward is fixed + some TX fees var). so it’s not a lottery.
    - lottin 5y ago
      Right. It's a thing where you have to guess a secret number, and the winner gets a prize, but it's definitely NOT a lottery.

The bitcoin consensus mechanism is literally a lottery in which the winner gets to decide what the "consensus" is. I don't know about "revolutionary"...

by lottin 5y ago

The bitcoin consensus mechanism is literally a lottery in which the winner gets to decide what the "consensus" is. I don't know about "revolutionary"...

rantwasp 5y ago

is it though? the “lottery winner” in your case assembles a block with transactions from the transaction pool (ie you don’t just make shit up. you are taking useful transaction that people are making them and capturing them into the chain) So the winner does not decide much, except maybe what transactions to select (spoiler alert: the transactions with the highest fees are normally selected). The consensus is in the sense that: you wanted to create a transaction and that transaction is captured and everyone in the network sees and agrees that the transact happened. The miner cannot alter your transaction. Other nodes in the network cannot arbitrarily reject it. You cannot simply claim you didn’t do it after the fact.

lottin 5y ago
> everyone in the network sees and agrees that the transact happened Why would everyone agree that the transaction happened?
- rantwasp 5y ago
  everyone == bitcoin nodes that each keep a copy of blockchain locally. once a block is mined it is propagated through the network and it’s verified by all the nodes that see it. In effect, when you get the block and you append it to your local blockchain after verification you agree that the transaction that happened in that block happened.
  - lottin 5y ago
    Yes, but the question is why would all the nodes agree that the transaction has happened. What's stopping them from disagreeing?
    - Arnavion 5y ago
      They're welcome to disagree. I can write a node that creates a chain with blocks that only contain some transactions of my choice and then broadcasts it. For nodes that only have access to my chain, they will also go with my chain. This is why being connected to multiple nodes is important. For nodes that have access to both my chain and the rest of the world's chain, they will go with the chain that has the most work put into it, because that is the one that is clearly supported by the majority computation power. It's irrational to go with the chain that has less power, because the entities that created the chain with more power can easily overwrite the chain with less power by virtue of having more power. Unless I happen to have more computation power than the rest of the world, the chain with more work put into it isn't going to be mine, which is why it's important that global computation power isn't consolidated into a single miner.
      - rantwasp 5y ago
        hmm. it’s not necessary more power. Sometimes it’s luck if you are talking about chains that are the same except the tip where they differ by 1-2 blocks.
      - lottin 5y ago
        > It's irrational to go with the chain that has less power, because the entities that created the chain with more power can easily overwrite the chain with less power by virtue of having more power. This basically means the entire bitcoin network depends on the entities that have the most computer power behaving correctly, am I wrong?
        Arnavion 5y ago
        That is correct. As I wrote in [1], the situation where the majority power becomes irrational is a doomsday scenario for bitcoin. [1]: https://news.ycombinator.com/item?id=28020592 https://news.ycombinator.com/item?id=28020592
        lottin 5y ago

FabHK 5y ago

> The bitcoin consensus mechanism is literally a lottery It is, but with the probability of winning proportional to the "work" you put in. That is crucial.

lottin 5y ago
Just like any lottery. The more tickets you buy the higher the probability of winning a lottery. In the bitcoin lottery the tickets are cpu power.
- rantwasp 5y ago
  not a lottery. in case of a lottery, when you have the winning numbers you go to a central authority that manages the whole thing and you claim the winnings. Also, in case of a lottery the winnings are a share of what has been put into buying the tickets. also, lotteries can go a long time without having a winner for the jackpot. Also for lotteries, usually there is a tiered winning structure and what you win on is fixed (ie the numbers) for bitcoin there is no central authority. the reward for winning is “fixed” and claiming the said reward is dependent on a network that validates that you indeed have the work that incorporates pending transactions into the blockchain. also, “winning” happens at regular intervals of time (average 10 minutes based on difficulty), and what you’re winning is somewhat fixed (the block reward is fixed + some TX fees var). so it’s not a lottery.
  - lottin 5y ago
    Right. It's a thing where you have to guess a secret number, and the winner gets a prize, but it's definitely NOT a lottery.