Homework on Bitcoin Transactions and UTXO - Questions

Blockchain and Bitcoin 101
#5687

1. Describe what Unspent Transaction Outputs (UTXO) are.
UTXO’s are the currency amounts of output (sender) wallets to the input (receiving) wallet that that defines the amount the input wallet is able to send. In simpler terms, it’s the “sum of funds” a wallet has.

2. What would happen if you don’t have any single UTXO that is large enough to cover for your transaction?
The transaction will fail, as the nodes on the blockchain will deny any transaction that doesn’t have enough UTXO.

3. How would a bitcoin wallet specify the transaction fee when creating a transaction?
A bitcoin wallet specify’s a transaction fee from the difference of the input minus the output; but what the wallet is doing is checking the network for current transactions and calculating a fee that will get the transaction processed the fastest.

4. How could you use the notion of transaction inputs and outputs to increase privacy in your transaction?
Wallets are anonymous online, there’s no way of knowing who has access to which wallets. This anonymity provides extra privacy, where you could even send funds to another wallet you own.

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#5688

You can use multiple UTXOs as inputs to a new tx. If that isn’t enough to cover your transaction then your transaction would be refused.

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#5689
  1. UTOXs are the inputs in your wallet or outputs of a transactions, all of the together built your wallet balance.
  2. The transaction would not be valid.
    3.Compare it to current transactions on the blockchain and choose an optimal amount.
    4.creating different adresses, espescially for the the outputs.
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#5690

You can use multiple UTXOs as inputs to a new tx. If that isn’t enough to cover your transaction then your transaction would be refused.

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#5691

good your adding some information i missed out, gracias!

#5692
  1. Unspent Transaction Outputs are inputs from transactions that are sitting unspent in wallets.
  2. If you don’t have any “single” UTXO that is large enough for a transaction, then it will combine multiple UTXO’s to cover said transaction. If theres not enough even then, then the transaction will not go through.
  3. The transaction fee is the difference between the inputs and the outputs in a transaction. The wallet will compare fees with the blockchain and give you a fee that will enter the blockchain as fast as it can.
  4. When you make a transaction, on face level you do not personally see the behind the scenes at all. Your wallet chooses which UTXO’s to use as inputs, to combine or not combine into a transaction. When they come out on the other side of the transaction, you would get a different output. Everything is scrambled when it goes through a transaction.
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#5693

Thank you for adding to this!

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#5694

Hello!

  1. UTXOs are transactions within a wallet that exist within a block that represent the amount of bitcoin held in that wallet based on received bitcoin from previous transactions.
  2. If you do not have a single UTXO that is large enough to cover the desired transaction, the miners will reject your transaction and it will not get onto the blockchain.
  3. A wallet specifies a transaction fee as the inputs equalling the output plus the fee.
  4. Inputs and outputs provide excellent privacy in transactions because there is no way to tell where the addresses exist or whom they belong to.
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#5695

You can use multiple UTXOs as inputs to a new tx. If that isn’t enough to cover your transaction then your transaction would be refused.

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#5696

  1. Describe what Unspent Transaction Outputs (UTXO) are.
    A Wallet constructs a Transaction, using UTXOs (Unspent Transaction Output).
    A Blockchain is a database of pluses/minuses that tracks UTXOs, where INPUTS are old OUTPUTS from previous transactions. Your Wallet (holds your PRIVATE key) will query the Blockchain on which UTXO this PRIVATE key can spend.

  2. What would happen if you don’t have any single UTXO that is large enough to cover for your transaction?
    As the blockchain WILL NOT summarize what you have in total in your Wallet, your Wallet’s role sums together all the UTXO OUTPUTS from previous Transactions and shows you your TOTAL BALANCE (e.g., User0a=0.5 BTC, User0b=0.2 BTC, User0c=0.3BTC and totals User1 WALLET to 1.0 BTC).
    The rule is User1 has to OUTPUT entire 1.0 BTC (e.g., Transaction to User2=0.7 BTC and User1=0.2 BTC back to itself and 0.1 BTC TRANSACTION Fee).

  3. How would a bitcoin wallet specify the transaction fee when creating a transaction?
    INPUTS = OUTPUTS + TRANSACTION Fees (implied). So, 0.5 BTC + 0.2 BTC + 0.3 BTC = 1.0 TOTAL INPUTS = (User2=0.7 BTC + User1=0.2 OUTPUTS) + 0.1 BTC TRANSACTION Fees. If the sum of all INPUTS aren’t enough to cover your TRANSACTION and TRANSACTION FEES, then your transaction would be refused.

  4. How could you use the notion of transaction inputs and outputs to increase privacy in your transaction?
    The Transaction is very private as Wallets are anonymous online. There’s no way of knowing who has access to which Wallets. This anonymity provides extra privacy, where you could even send funds to a different Wallet you own.

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#5697

1.) The UTXO is my balance of coins in my wallet. When i send someone else throw the blockchain then this is my input and the reciver gets the UTXO minus the fees.

2.) i cant send the transaction to the blockchain.

3.) He specify´s the fees from to last Input to the Output.

4.) you can have several outputs from one input.

#5698
  1. UTXOs are the balances left in one’s wallet.
  2. Your wallet calculates all UTXOs together until you have enough to cover the tx.
  3. The tx fee is calculated by input-output.
  4. You can create mu7ltiple outputs to different addresses.
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#5699

  1. UTXOs are the total number of funds on the blockchain allocated to your private key which are yet to be spent

  2. If you don’t have any one UTXO that is large enough to cover your transaction, your wallet will add multiple UTXOs (of specific coin/token) to cover the new transaction output, spend the required amount, then send the remainder (change) back to you minus the transaction fee

  3. The Bitcoin wallet figures out the fee which will be most successful in getting your transaction onto the blockchain quickly by taking into consideration the recent fee history of other successful transactions - Bitcoin miners are incentivised to choose transactions with the highest fees

  4. Increased privacy of transactions occurs with the ability to send inputs to multiple outputs, meaning that it’s difficult to establish where the funds went - e.g. someone could be just sending funds to multiple different addresses they themselves hold

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#5700
  1. Describe what Unspent Transaction Outputs (UTXO) are.
  • UTXOs are Bitcoins transferred to a node (becoming inputs of a transaction), which have not been processed to an output of that transaction yet.
  1. What would happen if you don’t have any single UTXO that is large enough to cover for your transaction?
  • I can combine multiple inputs to a transaction to cover its value.
  1. How would a bitcoin wallet specify the transaction fee when creating a transaction?
  • The wallet will either let you to propose a fee or it will check the blockchain and it will chose a reasonable fee to get the transaction done in a fast way.
  1. How could you use the notion of transaction inputs and outputs to increase privacy in your transaction?
  • Inputs and outputs are already encrypted so there is no way to identify an individual unless you do not know his/her BTC address.
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#5701
  1. UTXO’s are inputs received and yet unspent
  2. If my UTXO is too small to cover a pending transaction then the transaction can not be completed and the UTXO’s will remain in my wallet for the interim… waiting for more inputs to arrive before I can complete the intended transaction.
  3. The transaction fees is specified by the difference between the inputs received and the UTXO that is available on hand.
  4. Transaction inputs and outputs are large alphanumeric codes that are autonomous… no way to tell who is behind the input(s) or output(s)… and a single input can be splintered off into an indefinite number of outputs (that cumulatively add up the the amount of the input less any fees incurred)… ie the more outputs from a single input the greater the difficulty in trying to connect the owner(s)
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#5702 
Describe what Unspent Transaction Outputs (UTXO) are.

UTXOs are the unspent amounts from a previous transaction.

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

The wallet looks at all UTXOs to meet the demand of the transaction, therefore using all of the available UTXOs to sum the requested transaction. If the sum of all UTXOs is less than the requested transaction, the transaction will not execute.

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

The transaction fee is calculated from the sum of inputs minus the outputs of a transaction.

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

One could increase privacy by using different addresses for each transaction on the receiving end.

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#5703
  1. Its the balance on the wallet after receiving funds.
  2. The transaction wont be succesful
  3. Its not specified by the wallet rather by subtracting the spent output from the UTXO
  4. You can use different addreses and split it to them
#5704

You can use multiple UTXOs as inputs to a new tx. If that isn’t enough to cover your transaction then your transaction would be refused.

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#5705
  1. Describe what Unspent Transaction Outputs (UTXO) are.
    Transactions that have been received by your wallet by not yet spent or output by your wallet
  2. What would happen if you don’t have any single UTXO that is large enough to cover for your transaction?
    All UTXOs would be sent out of your wallet and the difference of your transaction minus fees would be sent back to your wallet/another wallet you control
  3. How would a bitcoin wallet specify the transaction fee when creating a transaction?
    TX fees are determined by the wallet based on previous tx fees on the blockchain based on the requested speed of the tx or best possible path for the tx
  4. How could you use the notion of transaction inputs and outputs to increase privacy in your transaction?
    The transaction shows multiple outputs and nobody knows for certain which outputs were sent back to your individual wallet
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#5706
  1. Describe what Unspent Transaction Outputs (UTXO) are.

A transaction has a input, and a output. The output is unspent, until it is used as a input in another transaction. All the UTXO that a private key can use, makes up the total amount of BTC that that particular private key can use as input for its on transaction.

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

You will use several smaller UTXO, and then construct the TX to send the change back to you minus the TX fee

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

IT would take the difference on what you sent, and what is sent back to you, to specifi the transaction fee.

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

You can not now who controls the private keys to the outputs. The can be going back to a wallet the sender controls.

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