Homework on Bitcoin Ecosystem - Questions

Blockchain and Bitcoin 101
#1005

Hi there! Actually, when you sign a transaction, it is broadcasted or shared with the rest of the nodes in the network and stored in the mempool. The mining process comes after this.

Hope this helps!

Felipe.

#1006

1.) The difference between an SPV and a full node is a full node contains the whole blockchain while an SPV contains transactions relevant to the blockchain so it has to connect to the full node when it needs to access the blockchain.

2.) When a transaction is broadcasted itā€™s sent out to the network, all the other nodes will see it, validate it, then distribute it throughout the network.

3.) Miners basically pick the transactions with the highest feeā€™s to add to the next block.

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#1007

1. What is the difference between a SPV (simplified payment verification) and a full node?
SPV can verify if transactions has been added in the blockchaine, without downloading the entire blockchaine. Full Node stores the entire blockchain and updates continuously, validate or reject newly created blocks, listen and propagate to the network, put transaction into the mempool.

2. What does it mean when a transaction is broadcasted?

When transaction is made, it is propagated to the network. Broadcast, can be described when a node listens this transactions form a closest node to it, and broadcast it further to its peers, until all nodes are updated.

3. How does a miner pick which transactions that gets added to the next block?

Miners picks a transaction from a mempool, the one with the highest fee.

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#1008

1 - SPV do not have full copy of the database. it has to query a node for that
2 - the transaction is copied to all the nodes for processing
3 - the one with the higher fee goes first

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#1009

Mauro:
The miner chooses the chain with most PoW, or the longest chain.
Thank you for bringing it to my attention.
Keep up the good work!

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#1010
  1. SPV has only a partial version of the blockchain stored, and needs to communicate with a full node to verify if everything is OK.
  2. it means that that a wallet created output utxo that is sent to the network
  3. Usually by the feeā€¦ higher the fee
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#1011

  1. An SPV does not have a full copy of the blockchain and can only query it via connection to full node.

  2. It means that a transaction is added to the mempool for miners to include in their blocks.

  3. Miners tend to pick transactions with the highest fees.

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#1012

  1. What is the difference between a SPV (simplified payment verification) and a full node?
    A: An SPV does not have a full version of the blockchain, wile a full node does. An SPV can generate transactions while a full node cannot.

  2. What does it mean when a transaction is broadcasted?
    A: A transaction is broadcasted from a wallet or an SPV signing the tx with the private key and communicating that to the network. It then enters the mempool where a miner will put it in a block to be mined.

  3. How does a miner pick which transactions that gets added to the next block?
    A: Miners will likely pick the transactions that give them the highest reward for mining that block. (Tx fees + the block reward).

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#1013

1.SPV has record of the transactions and a full node has the complete blockchain.

2.The node accepts the transaction and propagates to the whole network.

  1. Miner pick the transactions with the higher fees.
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#1014

Hi there!! Actually, both nodes can generate transactions, as they both act like wallets, storing private keys to be able to sign txs.

Felipe.

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#1015

  1. A node contains all data for the blockchain and is part of consensus. A SPV must always refer to a node for UTXOs and other data because there is no copy of the network.

  2. When a transaction is broadcasted it means the data is sent across the network by being entered into the mempool.

  3. A miner chooses a transaction the same way any of us would. That which benefits them the most (fees for profit etc).

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#1016

1.) A SPV does not have a copy of the full blockchain and has to be connected to a node to do so.
2.) It is where all the nodes are talking with each other about a transaction.
3.) Transactions are stored on the mempool, the ones with the higher transaction fees are chosen first to be mind.

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#1017
  1. An SPV doesnā€™t contain a full version of the blockchain but references a full node for this.
  2. When a wallet creates a transaction it announces it to the network by propogating it across all available nodes
  3. Miners choose transactions based on the best reward (highest fee) first.
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#1018

Homework on Bitcoin Ecosystem - Questions

What is the difference between a SPV (simplified payment verification) and a full node?

  • difference is that a SVP node does NOT have the full copy of the blockchain which a full will have

What does it mean when a transaction is broadcasted?

  • broadcasted means that the transaction is send accross the network and is put in the mempool so it can be picked up by a miner

How does a miner pick which transactions that gets added to the next block?

  • preferable it choose the transaction with the highest fees
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#1019

Yes, all nodes accept the longest chain. But how does the miner pick the transactions that need to be added from the mempool to the block? If we have 200 transactions in the mempool and we can only fit 100 in the block, how would the miner prioritize them.

All your answers are correct, but they donā€™t answer the actual question. Hope you donā€™t mind. :smiley:

#1020

There is no predetermined place when we broadcast a transaction. When we broadcast a transaction it propagates throughout the network, reaching every node that will add the transaction to their mempool. :slight_smile:

#1021
  1. SPV store only private key and need to be connected to node to perform transaction
  2. node accept transaction and propagate to network of nodes
  3. miners pick up transactions from mempool with the highest transaction rate per bit.
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#1022

  1. A full node contains a full local version of the blockchain, however a SPV does not and must connect to a full node to query the blockchain

  2. When broadcast, a transaction is propagated through each node in the network

  3. The miner picks transactions from the mempool based on the highest fee

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#1023

1 - An SPV does not have a full version of the blockchain, and therefore queries a node when it needs to make a transaction.

2 - It means it is included in the mempool of all the nodes in the network.

3 - Most likely the miner will pick the ones with higher fees for their size in bytes.

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#1024

  1. What is the difference between a SPV (simplified payment verification) and a full node?
    SPV is on a mobil phone and dosenā€™t have a full copy of the blockchain stored locally. It doesnā€™t store all UTXOā€™s and therefore needs confirmation from a full Node before validation.

  2. What does it mean when a transaction is broadcasted?
    Nodes or Miners adds TX to the Mempool.

  3. How does a miner pick which transactions that gets added to the next block?
    A Miner goes for the TX with the highest fee.