Building transactions with ethereumjs-tx and I'm confused as to why the from address is not included in the transaction. The transaction parameters are:
• nonce - transaction nonce
• to - to Address
• value - amount to be sent
• chainId - EIP 155 chainId - mainnet: 1, ropsten: 3
And the private key is used to sign the constructed transaction. But how does the ethereum network know from who to deduct the money from?