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When I create a signed transaction on my offline computer and then broadcast it on my online computer. What hinders a node to broadcast it again after my transaction is included in a block?

marked as duplicate by Ismael, Achala Dissanayake, Richard Horrocks, flygoing, Roman Frolov Jan 26 at 1:27

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I already found it out in the meantime. The nonce prevents double spends. Google Ethereum tx nonce to get more information.

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