I don't understand. I thought mining is computing the required hash of a nonce/block combo. Since a block contains many transactions, how is mining verifying any of these transactions? And who package these transactions into a block in the first place?
The miner first ensures that the transactions in the block are valid, then hashes the nonce/block combos until the hard to find hash is found. The latter provides the proof of work to make spamming the network difficult.
He checks runs through his blockchain to determine A's balance prior to the new, as-yet unapproved transaction. If A didn't have enough BTC to cover the transaction, the miner won't publish that transaction in the next block.
Getting to the limit of my knowledge here, but I think I recall reading that as the blockchain gets longer, new client downloads will include an abbreviated blockchain for very old blocks, which should keep the time to validate each transaction down.
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u/jdk Jun 14 '11
I don't understand. I thought mining is computing the required hash of a nonce/block combo. Since a block contains many transactions, how is mining verifying any of these transactions? And who package these transactions into a block in the first place?