Homework on Bitcoin Transactions and UTXO - Questions

You can use multiple UTXOs as inputs to a new tx. If you don’t have enough your transaction would be declined.

  1. UTXOs are the unspent output from the past transaction.
  2. If you don’t have a single UTXO that is large enough to cover your transaction it wall add up all UTXOs and if you still don’t have enough it will be declined.
  3. To find the bitcoin transaction fee when creating a transaction you take the total of the inputs minus the total of outputs.
  4. To use the notion of transaction inputs and outputs to increase your privacy you can use different addresses when receiving transactions.
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1. Describe what Unspent Transaction Outputs (UTXO) are.

Bitcoin uses the term UTXO to represent the quantity of bitcoins available to be spent in an individual’s account. Generally, the term UTXO can be understood as the amount of digital currency in an account that is “unspent” and available. The digital amounts remaining and available in an account are referred to as “outputs”. This is why we call the amount of (unspent) digital currency in an account a UTXO (Unspent Transaction Outputs).
It is also worth noting that the sum total of an accounts balance of digital currency can be made up of numerous “outputs” each representing a different numerical amount/quantity of bitcoin.
When a transaction is first initiated that requires a specified amount of Bitcoin, all existing outputs in the account are summed up in order to determine if there is a sufficient balance available to complete the transaction. If the balance in the account is available and is sufficient, then the transaction is created and and processed. The wallet then starts broadcasting the transaction to the nodes on the network.

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

Your wallet adds all of your UTXOs together. If the account has enough UTXOs the transaction would be processed. If not, it will be rejected/invalid.

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

The wallet would calculate the difference between the sum of the inputs minus the sum of the outputs.

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

When initiating a transaction, utilize many different addresses (that also belong to you) when sending and receiving transactions.

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Unspent transaction outputs are the sums of the transactions you have received, but they are not added to be one large sum and are instead kept separate.

UTXOs are grouped in that case, which allows the transaction to happen and the fees to be paid. The change from the transaction is then returned to you as a UTXO.

The transaction fee is found by your wallet by measuring recent transaction fees so that your transaction goes through fast enough, but at the same time, you don’t pay exorbitant prices because they will not significantly affect time.

Using many smaller UTXOs to pay for a transaction and receiving the change as many small UTXOs.

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  1. UTXO - amount avalible to send.
  2. Wallet will bring several UTXOs, send the required amount to address and then send back the rest amount of BTC minus fees.
  3. Input minus output.
  4. By using different wallets?
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  1. UTXO are the outputs of a transaction and the inputs of another transaction. The Bitcoin network doesn’t track your total balance, rather it tracks if all inputs are equal to outputs
  2. It wouldn’t proceed
  3. It chacks the blockchain and previous transactions and it will be calculated for you. Transaction fee = input - output
  4. By splitting up a transaction into smaller ones using different transactions and addresses and so on
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  1. A UTXO is the unspent amount of crypto a user receives that can be spend over a period of time.

  2. Your wallet and the blockchain would not allow the transaction to happen because there would not be any UTXO Available to spend.

  3. It’s the difference between the inputs and the outputs of a transaction.

  4. Use different addresses

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You can use multiple UTXOs as inputs to a new tx. If you don’t have enough your transaction would be declined.

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  1. UTXOs are outputs from transactions that are in your wallet and from them you can calculate your account balance, if we send them further, they become the input of the next transaction.
  2. The transaction will be declined.
  3. transaction fee = inputs - UTXO
  4. By using different accounts when you want to transfer transactions to yourself.
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  1. Describe what Unspent Transaction Outputs (UTXO) are.
    UTXOs are outputs sent to a wallet (public key) that are used to as inputs for future transactions sent from that wallet.

  2. What would happen if you don’t have any single UTXO that is large enough to cover for your transaction?
    Your wallet would take take the some of UTXOs sent to your address to complete the transaction and if there is not enough the transaction will not be made.

  3. How would a bitcoin wallet specify the transaction fee when creating a transaction?
    Fee is specified by the difference between total inputs and total outputs. Wallets will recommend a transaction fee that will allow the transaction to be added to the blockchain quick enough to be successful by looking at recent transactions.

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

By sending multiple transactions to public keys owned by yourself, the public will not know that there is a single owner for the multiple addresses.

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  1. UTXOs are the amount of money that you have not spent and that you can afford to spend
  2. you send a transaction that sums the amount back to yourself then make the transaction
  3. Either its automatically suggested based on previous fees of other transactions or you can manually specify it, if it is not enough it will be refused though
  4. If every time you make a transaction part of the money goes back to yourself people can’t know the exact amount that you spent thus its more private
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  1. Total of UTXO is the wallet balance.
  2. Use more then one UTXO.
  3. A bitcoin wallet recommend a reasonable fee, bases on the current and previous transaction fees.
  4. In each single transaction the blockchain produces a new address for me. if u are changing the addresses it makes it hard to understand who is the owner of the wallet.
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You can use multiple UTXOs as inputs to a new tx. If you don’t have enough your transaction would be declined.

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

This is basically your balance of BTC, they are the amount of unspent BTC you have. This is the amount you can spend on an other transaction.

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

  2. How would a bitcoin wallet specify the transaction fee when creating a transaction?
    The fees are the amount of input minus the amount of output.

  3. How could you use the notion of transaction inputs and outputs to increase privacy in your transaction?
    With the notion of imput and output, it’s difficult to track what goes to who. The transactions are with anonymous adresses, you can sent back the BTC to yourself.

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  • It’s an output that it wasn’t spent yet. Composes the balance of one.

  • Than your wallet will sum the numbers of UTXO that are necessary to cover the transaction and gave back the amount that exceed the transaction cost to you (like a change)

  • Input minus output

  • The concept it’s really safe and aim the privacy of users because from outside, even being public, someone will never gets who’s participating in that specific transaction; it might deduce, but it’s real hard to figure out what’s happening, what’s the real value of that specific output and what’s value is coming back to the original transaction launcher…

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You can use multiple UTXOs as inputs to a new tx. If you don’t have enough your transaction would be declined.

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  1. Describe what Unspent Transaction Outputs (UTXO) are.
    UTXOs are all the input that have not been spent.
  2. What would happen if you don’t have any single UTXO that is large enough to cover for your transaction?
    The transaction would not be executed.
  3. How would a bitcoin wallet specify the transaction fee when creating a transaction?
    Fee = Input - Output
  4. How could you use the notion of transaction inputs and outputs to increase privacy in your transaction?
    I would add output to my other wallet in transactions.
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You can use multiple UTXOs as inputs to a new tx. If you don’t have enough your transaction would be declined.

  1. A UTXO is the balance(s) that you have in your wallet.
  2. If you don’t have enough for the transaction on your balance, it will be declined.
  3. BTC finds the trans. fee by subtracting the in & output to generate the best fee.
  4. You can increase your privacy by receiving on a newly created address.
  1. Describe what Unspent Transaction Outputs (UTXO) are.

UTXO’s are the unspent transaction amounts that have been sent to you or others on the blockchian. They’re stored on the Blockchain and your wallet uses your private keys to add them up to show your balance.

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

Your wallet would add up multiple UTXO’s to cover the transaction cost, and send the difference, if any, back to you. If there wasn’t enough UTXO’s to cover the transaction amounts, the transaction would be invalid.

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

The Bitcoin wallet will query the blockchain to see what the fees are based on similar transactions and give the best one at that moment in time. The wallet may also give you several choices for the transaction. (Input-Output = Fees)

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

Privacy is already built into the transactions because no-one knows who owns the addresses in any transaction. (Unless you’re KYC’d up the wazou) But, if you must, create multiple addresses to send the remaining amounts, if any, to them from the transaction.

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