Homework on Bitcoin Transactions and UTXO - Questions

Blockchain and Bitcoin 101
#542

1- An UTXO is an output generated by an input in a certain transaction, Once you receive this transaction it becomes your unspend balance in you wallet.

2- The transaction would not be valid, the public ledger won´t accept this transaction because it knows you don´t have enough UTXOs to cover the transaction.

3- The input has to be the same as the output + the fees, so it´s quite simple, to calculate the fee your wallet does the following, Fee= Input - Output.

4- Many adresses and output can result from the same input.

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#543
  1. Describe what Unspent Transaction Outputs (UTXO) are.
  • UTXOs are the unspent outputs of a transaction. All the UTXOs in your wallet make up your balance.
  1. What would happen if you don’t have any single UTXO that is large enough to cover for your transaction?
  • Then you would need to use additional UTXOs to cover the amount (any over payments can be sent back to yourself as change). If this is not possible then the transaction will not go through.
  1. How would a bitcoin wallet specify the transaction fee when creating a transaction?
  • The transaction fee is the difference between the inputs and outputs. The fee can be increased to move your transaction up the queue.
  1. How could you use the notion of transaction inputs and outputs to increase privacy in your transaction?
  • It is possible to create a transaction that will distribute your funds into different wallet addresses. From the outside it is not possible to know if these are different addresses in the same wallet or not.
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#544

  1. UTXO are the balance of the wallet someone has the private keys for. The sum of all UTXOs of the wallet is the amount someone can spend as the input of a new transaction

  2. The transaction would not get validated by the other participants in the network and therefore the transaction would get rejected

  3. A transaction consists always of the formula: inputs (the UTXOs of a wallet) =output- transaction fee. That means the transaction fee is calculated by the subtraction of the input - the output.

  4. The input of a transaction is always equal to the output+transaction fee. When you sending someone not the whole amount of your wallet balance, the rest of the amount will be “send” back to your wallet. To avoid receiving the rest of the money to your old wallet, I can generate a new address and send the unspent bitcoins to the new address. This increases the privacy because no one knows who the owner of this new address is.

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#545

Describe what Unspent Transaction Outputs (UTXO) are

  1. UTXO’s are BTC transactions that you have received that are simply lying around until you spend them. The sum of UTXO’s is your wallet balance.

What would happen if you don’t have any single UTXO that is large enough to cover for your transaction?
2. The wallet will spend all the BTC in all UTXO’s you have and will split that total between the recipient, the TX fee and the ‘change’ you receive to another address allocated to you. Inputs =Outputs + transaction fee. If the total UTXO is less than the ouput it will be rejected.

How would a bitcoin wallet specify the transaction fee when creating a transaction?
3. Depending on the type of wallet you have the fee will either be worked out automatically based on the fee of the previous transactions or you get a choice of fee depending on the speed of the transaction you require. UTXO input - output = fee.

How could you use the notion of transaction inputs and outputs to increase privacy in your transaction?
4. Use different receiving addresses for each transaction, and choose outputs that are less than your total balance so you receive ‘change’ to yet another address (that is yours).

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#546

  1. Describe what Unspent Transaction Outputs (UTXO) are.
    Unspent Transaction is how cripto currency described on the blockchain until it is spent the outputs then becomes someone else unspent Transaction.

  2. What would happen if you don’t have any single UTXO that is large enough to cover for your transaction?
    if you don’t have enough it will be declined. otherwise UTXO will combine themselves to match or exceed the transaction amount.

  3. How would a bitcoin wallet specify the transaction fee when creating a transaction?
    a user can specify a fee or a wallet could calculate fee’s to receive a better transaction time.

  4. How could you use the notion of transaction inputs and outputs to increase privacy in your transaction?
    a wallet will keep your personal identity separate from your transaction on blockchain ledger.

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#547

  1. UTXOs are the BTC transactions received, which in aggregate is equal to the balance.

  2. The wallet will use multiple UTXOs to cover the sum of the transaction and fees. The remaining balance left will be sent back to wallet to another address allocated to the wallet.

  3. The wallet will calculate a fee based on prior transactions on the blockchain.

  4. Multiple UTXOs are inputted and with a transaction there are multiple outputs. If the outputs are to different addresses then it would be harder for others to track.

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#548

  1. Unspent Transaction Outputs (UTXO) represent an output from a previous blockchain transaction that has not yet been “spent,” or rather, an output that not yet been applied as an input to a new transaction.

  2. The wallet will assess your available UTXOs and aggregate until it can input a sum greater than the desired output, and send the remaining funds back to you.

  3. The transaction fee defines the difference between the input and output totals, and the wallet often determines this figure with an audit of contemporary transaction fees by querying the blockchain. This fee is automatically transferred to the address of the miner.

  4. You can increase your level of privacy by owning multiple wallets and transferring BTC through multiple UTXOs, thereby generating a transaction with more inputs and outputs than necessary in an effort to shroud which output addresses represent the intended recipient party and which addresses may or may not belong to you.

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#549

1
A single UTXOo is the recording in the bc about the output transaction with my (for ex) address (ie public key) as a final beneficiary. It will have a certain amount of BTC recorded.
In order to visualize the balance, a wallet sum all the Unspended TXions Outputs associated with the wallet’s addresses on the bc.

2
It would be denied by the wallet.
On the contrary, if I only have bigger UTXOs, similarly as I ask the rest to the cashier, the wallet executes a output transaction constructed where the “rest” amount have one of the wallet’s addresses as beneficiary.

3
The wallet subtract part of the satoshi amount as miner’s incentive fee: Beneficiary input will be a wallet’s UTXO-fee
The amount of the fee is set in order to let the miner append the transaction to the block in a reasonable time. Bigger fee result in a faster transaction consensus.

4
A wallet can generate many addresses from a public key so it can propagate in the bc different address during every TX.

#550

1 utxo is like the balance in your wallet ( your wallet adds all the utxos and shows you your balance) they are also like the change you get after every transaction
2 use more thatn 1 utxo or if you dont have enough balance the transaction will not go though
3the fee is the difference between the input and output
4 if you use many inputs and outputs would be more difficult to track

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#551

UTXOs are “coins” that one received and did not yet spend. The sum of all UTXOs in one’s wallet makes up the balance.

Then the wallet would use more than one UTXO for the transaction’s input.

Most wallets automatically suggest a transaction fee that is low but also gets the transaction processed in a reasonable time. Fees and processing times increase if there are many transactions at the same time.

Privacy increases if the wallet always uses a new address for the remainder (the transaction output that goes back to one’s own wallet) of a transaction.

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#552

Hi Fabrice,

Yes using smaller UTXOs, in your inputs, & if the sum of all your utxo´s doesn’t cover the amount.
Then the transaction will fail.

thanks Fabrice.

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#553

  1. UTXOs are outputs of a previous transaction.

  2. Your wallet would add other possessed UTXOs to cover the amount + fee and generate the return utxo to your wallet.

  3. It would remain available for the miner an amount between total input and total output to be sent to his own wallet.

  4. Each and everyone could send returning utxos to a new controlled wallet that haven’t been in use before.

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#554
  1. UTXO is the bunch of output and inputs collection
  2. that means it will basically won’t work
  3. You wallet will give you the best fee options for your transaction in order to make your TX smooth and as fast as possible
  4. I can create and TX to myself or other accounts which I have access to
#555
  1. They’re output transactions sent to someone who has yet to spend amount attached to that transaction.
  2. Any number of UTXO’s can be used to construct a transaction to meet the value the you want to transact. Obviously you would have to have that amount of UTXO’s allocated to you in the first place.
  3. By assessing the fees recently used in the blockchain and calculating an appropriate fee which would ensure your transaction as added to the blockchain.
  4. As the sum of the inputs must equal the outputs (+ fees), any unspent bitcoin will come back to you. It is difficult to verify which part of the output is the one you’re spending and which is the one coming back to you.
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#556
  1. UTXOs are unspent transactions outputs that your wallet keeps track of and calculates
  2. Your transaction will be rejected by the system if you don’t have enough UTXOs
  3. Your wallet usually proposes the transaction fee itself based on the previous transaction fees in the block or you can also manually input fee
  4. As they are hashed it’s impossible to say who owns the wallet therefore your identity stays private.
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#557

1.) UTXOs are unspent outputs from the previous transaction.
2.) The blockchain keep all utxos and the wallet figure out the balance. If is not enough balance for the output the transaction is invalidated
3.) The fee is calculated from the remainder of all inputs minus the outputs of a transaction. input - output = Fee
4.) Use a different address for each receiving a transaction also can be send back to myshelf

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#558
  1. UTXO are ‘available’ satoshis to spend, they exist as the result or output from received transactions into your wallet pkeys
  2. means only you can not spend it until you get enough
  3. usually there is a variable value in [satoshi per byte] depending on the network transactions congestion and wallet would show the suggested_totalfee = [byte size]*[satoshi per byte] and would remove this fee value from the available ‘change-value’.
  4. you could mix/join several output payments in one transaction; also with coin-control you could use several utxo’s from several pkeys inside your wallet, also some wallets do have ‘coin-join’ option-services, and lastly if you were a miner with your own coding ability to incorporate your own transactions at will when you found a block for yourself you could simply remove all change addresses and this way your just found block would receive an untraced fees and change amounts from all the payments done into this block coinbase-tx utxo as block-reward +(fees+changes).
#559
  1. Describe what Unspent Transaction Outputs (UTXO) are.
    UTXOs are outputs from transactions sent to you, that you haven’t spent in any transactions of your own yet. Then these outputs become inputs in your next transaction.
  2. What would happen if you don’t have any single UTXO that is large enough to cover for your transaction?
    I have to use another UTXO (or more) so that the sum of the UTXOs cover the transaction. The excess is sent back to me as “change” (minus the fee).
  3. How would a bitcoin wallet specify the transaction fee when creating a transaction?
    The difference between input and output, it basically checks the blockchain for the amount of the fee.
  4. How could you use the notion of transaction inputs and outputs to increase privacy in your transaction? send transactions back to me using another address under my control.
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#560
  1. Describe what Unspent Transaction Outputs (UTXO) are.
  • UTXO is the unspend amound you have in your wallet.
  1. What would happen if you don’t have any single UTXO that is large enough to cover for your transaction?
  • You will not be able to pay the amound needed.
  1. How would a bitcoin wallet specify the transaction fee when creating a transaction?
  • The difference between input and output in your transaction.
  1. How could you use the notion of transaction inputs and outputs to increase privacy in your transaction?
  • Use serveral input and output adresses. Or just use a protocol with Minble Wimble added.
#561

1 - UTXO are unspent transaction ready to be used with your private key

2 - In case you don’t have a UTXO of the size of the payment the wallet will use multiple UTXO and send the difference bacj to you in a new UTXO.

3 - The transaction fee is specified in “sat/b”

4 - You could redirect your payment into other wallets before sending the actual transaction.