How Does a “Nonce” Prevent Signature Reuse in a Smart Contract Transaction?
A nonce, or "number used once," is a sequential counter associated with a user's account on an Ethereum-like blockchain. When a user sends a transaction, the nonce is included in the transaction data that is signed.
The network only accepts a transaction if its nonce matches the account's current expected nonce, and then increments the account's nonce. Since the signature is only valid for that specific nonce, the transaction cannot be replayed, as the nonce would be incorrect for any future transaction.
