What makes a transaction unique in-block?

DannyHamilton

legendary

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Quote from: Peter Lambert on February 05, 2014, 12:01:17 PM

If a miner tried to duplicate payments in the block it would be invalid and the block would be ignored by all the other miners.

No only all other miners, but all other peers as well. Every node would refuse to add the block to their own copy of the blockchain and would refuse to relay the block to anybody else.

davidpbrown

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Vires in Numeris

Quote from: Peter Lambert on February 05, 2014, 12:01:17 PM

If a miner tried to duplicate payments in the block it would be invalid and the block would be ignored by all the other miners.

Thanks, I was hoping for it to be that simple.

Peter Lambert

hero member

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It's all fun and games until somebody loses an eye

Quote from: davidpbrown on February 05, 2014, 10:49:43 AM

Can someone suggest, perhaps ELI5, how it isn't possible for a miner to see a transaction payment to themselves; duplicate it many times; and put those into a block that they confirm? That would be trying to suck the donating account dry, down to the modulus. How is each transaction unique, that miners cannot exploit them in the block they are creating? Obviously, trying that would still be a matter of luck in order they are the miner confirming the next block but still not clear to me, how it's not possible. I'm expecting that transactions can't be duplicated from one block to another because of some ?Merkle root signature of the existing tree or similar but how is in-block duplication prevented?

If a miner tried to duplicate payments in the block it would be invalid and the block would be ignored by all the other miners.

andytoshi

full member

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There are no accounts in bitcoin. Every transaction uses the full value of its inputs.

davidpbrown

sr. member

Activity: 531

Merit: 260

Vires in Numeris

Can someone suggest, perhaps ELI5, how it isn't possible for a miner to see a transaction payment to themselves; duplicate it many times; and put those into a block that they confirm? That would be trying to suck the donating account dry, down to the modulus. How is each transaction unique, that miners cannot exploit them in the block they are creating? Obviously, trying that would still be a matter of luck in order they are the miner confirming the next block but still not clear to me, how it's not possible. I'm expecting that transactions can't be duplicated from one block to another because of some ?Merkle root signature of the existing tree or similar but how is in-block duplication prevented?

Topic: What makes a transaction unique in-block? (Read 514 times)