Homework on Bitcoin Transactions and UTXO - Questions

Blockchain and Bitcoin 101
#4345

1 UTXOs are unspent transactions ouputs. They are the output of another transaction.
2 The wallet will use multpile utxos as inputs.
3. Sum of inputs minus sum of outputs
4 you could use multiple inputs and outputs.

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#4346

  1. Describe what Unspent Transaction Outputs (UTXO) are.

    Each UTXO is an unused Output from previous transactions, and as a whole UTXOs represent the entire wallet balance.

  2. What would happen if you don’t have any single UTXO that is large enough to cover for your transaction?

    While doing a transaction the rule is to always use the sum of UTXOs on my wallet.

    To clarify:

  • I have 2 UTOXs (0.4+0.5) in my wallet and want to buy something that costs 0.7
  • I will use both of my UTXOs in the transaction, send 0.7 to the seller and 0.2 back to myself

  1. How would a bitcoin wallet specify the transaction fee when creating a transaction?

    The Wallet will pick the best fee by verifying the blockchains previous fees and choose the one that completes the transaction faster. Some wallets allow for manual choosing.

    No matter the case, Inputs = Outputs + fees

  2. How could you use the notion of transaction inputs and outputs to increase privacy in your transaction?

    The more Inputs and Outputs are used in a transaction, the more private will it be, since it’s not possible to verify the receivers identity.

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#4347
  1. A UTXO is the result of a transaction for which one output (or the output) was sent to you. Basically as long as your wallet do not take that UTXO to compute a transaction, that amount is part of your balance.
  2. Your wallet is going to look for other UTXO which belong to you since the sum of the UTXOs is higher or equal to the amount of the transaction you want to carry out.
  3. Or is the owner of the wallet which decide how much BTC will be use as fee, or the wallet looking at the avarage transaction’s fees in the blockchain, will suggest you an amount which guarantee you that a miner will confirm your transaction.
  4. Some of the outputs can be redirect to sender (to another address which is own by him) so is even more difficult to figure out something related to a wallet.
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#4348
  1. Unused balance received from previous transaction that you can spend.
  2. You can use 2 utxo or more in order to complete your transaction…
  3. It won’t specify it. You can find it by subtracting output from input.
  4. By combining multiple inputs and outputs and generating new address for every transaction.
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#4349
  1. Are the inputs and outputs of a transaction.
  2. the transaction will not go through
    3.It will calculate it. input-output
  3. Use different addresses in each transaction.
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#4350
  1. UTXOs are previous transactions inputs sent to a Private Key that are not spent.
  2. The Wallet will pick 2 ore more UTXOs to use in the transaction, as multiple UTXOs can be used a single transaction.
  3. It doesn’t need to, it will be implied, as tx inputs = tx outputs +tx fee.
  4. One could use multiple tx inputs and multiple tx outputs (even if only a single TXO would be the actual tx, the rest would return to the same private key)
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#4351
  1. UTXO is the total balance in your wallet that has not been spent or transacted yet.
  2. The transaction will not go through as the nodes will not confirm it and miners will not include it in a new block.
  3. The wallet configures the transaction fee by figuring out the remainder of total of inputs minus the total of outputs.
  4. Create new output addresses every time transaction takes place for each utxos, making it more difficult to track.
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#4352
  1. Describe what Unspent Transaction Outputs (UTXO) are.

UTXOs are outputs from other transactions that you can use to create transactions and spend your bitcoin.

  1. What would happen if you don’t have any single UTXO that is large enough to cover for your transaction?

Your wallet can use more than one UTXO per transaction. If there is surplus bitcoin, it can send it back to you.

  1. How would a bitcoin wallet specify the transaction fee when creating a transaction?

The wallet scans the blockchain and calculates a reasonable fee based on the size of the transaction. Alternatively the user could nominate a fee. It appears as a separate transaction.

  1. How could you use the notion of transaction inputs and outputs to increase privacy in your transaction?

You could send bitcoin in multiple transactions to many different wallets, controlled by you or others. You could use paper/cold wallets. You could engage in ‘coin mixing.’

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#4353
  1. All transaction outputs from previous wallet addresses.
  2. All UTXO’s are summed up and sent out all at once, and the amount that isn’t part of the transaction is sent back to the sender’s wallet.
  3. By listing it as the difference between what came in and what went out.
  4. By controlling multiple wallets and sending to every one of them plus your intended recipient.
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#4354

1. Describe what Unspent Transaction Outputs (UTXO) are.
Transactions that have been signed by your private key, which are still available to be spent.
2. What would happen if you don’t have any single UTXO that is large enough to cover for your transaction?
Multiple UTXOs that are large enough to cover the transaction will be used, and the reminder will be returned back to your wallet.
3. How would a bitcoin wallet specify the transaction fee when creating a transaction?
It will take the difference between inputs and outputs
4. How could you use the notion of transaction inputs and outputs to increase privacy in your transaction?
Because an input can be split into multiple outputs, some of which represents transactions that are sent back to the original wallet, it is unclear which address belongs to another wallet not controlled by you, vs a wallet that is controlled by you.

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#4355
  1. Transactions are constructed through the use of UTXOs as inputs which are simply outputs from a transaction that has not been put to use. The sum of UTXOs indicates the wallet balance.
  2. Transaction gets declined.
  3. The wallet checks the blockchain and generates a fee accordingly. The fee is then equal to the input minus the output.
  4. Different addresses may be used as an output which may or may not belong to the same sender. These addresses have no correlation with one another, making it anonymous.
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#4356
  1. UTXOs are transaction outputs that are NOT inputs for another transaction.
  2. The transaction will not be added to the ledger.
  3. It is the difference between the total output and the total input.
  4. Essentially, many address inputs are used to pay several output addresses. As such transactions don’t appear to have a one to one relationship creating a situation where anyone could be paying anyone else.
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#4357

You can use multiple UTXOs as inputs to a new tx. If you still don’t have enough then your tx would not go through. :slight_smile:

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#4358

  1. They are the amount of funds that a wallet has available to spend. They are transaction outputs from previous transactions.

  2. You’d need to use more UTXOs so that the transaction amount is covered. Otherwise, it won’t be added to the blockchain.

  3. It will look at the blockchain and give you a fee that will throughput the transaction in a reasonable amount of time. It is the difference between the input and output.

  4. You could send the change UTXOs to many different addresses that you control. Because no one knows who the recipients are.

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#4359

  1. UTXO’s are all the transactions with unspent outputs.

  2. Your wallet would look for any other UTXOs linked to your private key that are large enough.

  3. Whilst you can sometimes manually set the fee yourself, most wallets will automatically offer various options depending on the speed you want the transaction to be confirmed at and the current level of activity on the network (i.e. size of the mempool).

  4. A transaction output could be to another address linked to a different wallet for which you also had control of the private key.

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#4360

Homework - UTXOs
Bitcoin Basics

Describe what Unspent Transaction Outputs (UTXO) are.
A transaction that comes in to and out from a wallet.

What would happen if you don’t have any single UTXO that is large enough to cover for your transaction?
The wallet takes then another UTXO and then sends you back the change.

How would a bitcoin wallet specify the transaction fee when creating a transaction?
The input minus the output.

How could you use the notion of transaction inputs and outputs to increase privacy in your transaction?
Multiple adresses that you control yourself.

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#4361
  1. UTXO’s are basically your account balances, the sum of previous inputs= what you are able to spend.
  2. Your tx would be rejected.
  3. The difference between the total input and the output= tx fee
  4. You could do multiple transfers in one transaction, as well as using virgin adresses to receive btc.
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#4362

  1. Describe what Unspent Transaction Outputs (UTXO) are.
    UTXOs are incoming funds to your wallet.

  2. What would happen if you don’t have any single UTXO that is large enough to cover for your transaction?
    When the transaction is constructed in the wallet, multiple UTXOs can be used as inputs as long as enough total quantity is available.

  3. How would a bitcoin wallet specify the transaction fee when creating a transaction?
    Input =Output+Tx fee

  4. How could you use the notion of transaction inputs and outputs to increase privacy in your transaction?
    You can have multiple outputs with some or all going back to addresses you control.

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#4363
  1. Unspent transaction outputs is the amount of your previous transactions available for spending, and their sum makes the balance of your wallet
  2. The transaction would be denied
  3. with the difference between the inputs and the outputs and verifying in the blockchain
  4. using a different address for each transaction
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#4364

  1. Describe what Unspent Transaction Outputs (UTXO) are.
    “Sent” transactions awaiting further instructions.

  2. What would happen if you don’t have any single UTXO that is large enough to cover for your transaction?
    Your wallet would use multiple UTXOs to complete the transaction, including paying the fee and sending remainder of funds to the address you dictate. If you didn’t have enough UTXOs in total, your transaction would be rejected.

  3. How would a bitcoin wallet specify the transaction fee when creating a transaction?
    Most can look at the blockchain to get an idea of recent fees and propose a reasonable fee to you for the transaction. Basic rule applies: Input = Output + Fee.

  4. How could you use the notion of transaction inputs and outputs to increase privacy in your transaction?
    By using multiple address and transaction amounts.

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