How is an payment transaction in bitcoin executed?


Most blockchain literature provides descriptions of miners solving problems and if successful adding a new block to the existing chain of blocks. There are nowadays other approaches with a similar procedure.

However it is not always clear how a payment from A to B is executed. Take the following example: A orders a payment of a certain amount of bitcoins to B; who makes sure that B receives his amount of bitcoins and where can the addition to B’s account be ascertained and similarly the reduction of the account of A?

    basically there are only transactions in bitcoin and in the whole bitcoin blockchain. The amount of money for wallet or account is calculate indirectly based on the unspent transactions that are associated to the account. So basically the balance of Alice does not exist explicitly, it is always indirectly calculated by the valid and unspent transactions that are associated to the account of Alice.

    So, if there is a new transaction, it propagated onto the network and validated by a miner and the balance is indirectly calculated based on the transactions.

    Dear Daniel,

    Thank you for your reply. I am nearly there.
    Do I understand it correctly that the validation by the miner implies an algo for subtracting the amount of bitcoins in the wallet of Alice and adding it to the wallet of Bob?