Homework on Blockchain and Mining Visually - Questions

Blockchain and Bitcoin 101
#4582

1 It is important that the blocks are cryptographically linked together because it ensure that the blockchain is immutable and secure. By linking the blocks together, it makes it impossible for someone to go back and change a previous block without also changing all of the subsequent blocks in the chain. This makes it much more difficult for someone to tamper with the blockchain.

2 The block structure in Bitcoin is designed to be secure and efficient. Each block contains a header, which includes a timestamp, a reference to the previous block, and a cryptographic hash. The block also contains a list of transactions, which are validated by miners. This structure ensures that the blockchain is secure and immutable, while also allowing for efficient and secure transactions.

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#4583

  1. For the purpose of security. Since each block is cryptographically linked to the subsequent one, if a transaction is changed somehow in a previous block, all the hashes of all the other blocks that follows changes, which produces a blockchain entirely different of what all the other nodes would have at that moment.

  2. The block structure is based on the hash of previous block + all the transactions inside the present block + the nonce that was guessed by the miner that is lower than that of the actual target number.

#4584
  1. Why is it important that the blocks are cryptographically linked together?

Security and prevent breaking the block and link of that transaction.

  1. What does the block structure look like in bitcoin

Block 1
Nouce 160057 (random numbers) guess until you get the hash.

Data: Tx a to b
Tx c to d
Tx e to f
Prev: 00000000000000000
Hash 100hkkpe2854849336 (final hash)

On the next block the final hash will be the previous hash.

#4585
  1. Cryptographic linking ensures that the blockchain is tamper-evident, as modifying a block would require changing subsequent blocks, which is computationally infeasible.
  2. A Bitcoin block consists of a block header with metadata and a list of transactions, including a coinbase transaction that rewards the miner
#4586
  1. Why is it important that the blocks are cryptographically linked together?
    it makes network secury dont bring any hackers
  2. What does the block structure look like in bitcoin?
    prehash hash transiction nonce who is lower than actual number
#4587
  1. To maintain the integrity of data within each block.
  2. Nonce + Tx data + previous hash = new hash
#4588
  1. Why is it important that the blocks are cryptographically linked together? to secure the network and avoid beeing rehashed
  2. What does the block structure look like in bitcoin? it includes the previsous hash from the previous block + transaction list + nonce.
#4589
  1. It is important that the blocks in a blockchain are cryptographically linked together because this ensures the integrity and immutability of the data stored in the blockchain. Each block in the chain contains a unique cryptographic hash that is based on the contents of the block and the hash of the previous block in the chain. This means that if any part of a block is altered, it will change the hash of that block and all subsequent blocks, making it easy to detect and reject any attempts at tampering with the data in the blockchain. This makes the blockchain a secure and trustworthy way to store and transmit data.
  2. The block structure in Bitcoin consists of a header and a list of transactions. The header contains metadata about the block, including its version number, the hash of the previous block, a timestamp, a nonce (a random number used to solve a cryptographic puzzle), and the current difficulty target for mining new blocks. The list of transactions contains all of the transactions that have been validated and added to the block, along with their associated inputs and outputs. Once a block is added to the blockchain, it cannot be modified or removed, ensuring the immutability of the data stored in the blockchain.
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#4590

  1. It is important that the blocks in a blockchain are cryptographically linked together because this linking provides the foundational security for the entire blockchain.

  2. The block structure in Bitcoin consists of several components:

  1. Block Header: This is a 80-byte structure that contains metadata about the block, including the block’s version number, the previous block’s hash, a timestamp, the Merkle root hash of all the transactions in the block, the target difficulty level, and a nonce.
  2. Transactions: This is a variable-length list of transactions that are being added to the blockchain. Each transaction contains information about the sender, the recipient, and the amount of Bitcoin being sent.
  3. Block Size: This is the size of the entire block, including the header and transactions, measured in bytes.
  4. Block Height: This is a numerical value that represents the position of the block in the blockchain.
  5. Merkle Root: This is a hash that is calculated by taking the hashes of all the transactions in the block and combining them in a specific way to create a single root hash. This provides a way for nodes to verify that a particular transaction is included in the block without having to download and process every transaction in the block.
  6. Nonce: This is a random value that is added to the block header to change the resulting hash value. Miners change the nonce value multiple times to try and find a hash value that meets the target difficulty level.
  7. Previous Block Hash: This is the hash of the previous block in the blockchain. This links the blocks together in a chain, providing the immutability and tamper-resistance that is characteristic of a blockchain.
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#4591
  1. Why is it important that the blocks are cryptographically linked together?

the cryptographic linking of blocks in a blockchain ensures data integrity, immutability, establishes a chain of trust, and supports consensus and security within the network. It provides tamper-evident protection against data modification, allows for independent verification, and fosters trust and reliability in decentralized systems

  1. What does the block structure look like in bitcoin?
    each block in the Bitcoin blockchain contains a header with important metadata, a list of transactions, and a unique identifier in the form of a block hash. This structure ensures the integrity, security, and consistency of the blockchain and enables efficient verification and consensus within the network.
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#4592
  1. Why is it important that the blocks are cryptographically linked together?
    To assure security of tranactions and protection against double spend and fraudulent changes in the blockchain.
  2. What does the block structure look like in bitcoin?
    Previous block hash + current transactions + nonce = hash
#4593

It is important because it makes it virtually impossible to tamper with.

There are three parts to the block structure

  1. The hash of the previous block structure
  2. The records of the transactions
  3. The nonce
#4594

[quote=“ivan, post:1, topic:8433, full:true”]
Homework on Blockchain and Mining Visually - Questions

  1. Why is it important that the blocks are cryptographically linked together?
    It makes miners spend more electricity and makes network secure.

  2. What does the block structure look like in bitcoin?
    Transactions, nonce, UTXO, block hash.

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#4595

1 Why is it important that the blocks are cryptographically linked together? To prevent fraud.
2 What does the block structure look like in bitcoin? Previous hash, transactions list, nonce.

#4596
  1. It is important for the blocks to be cryptographically linked together to ensure that no bad actors can change any previously mined blocks without invalidating the network.
  2. The block structure of Bitcoin consists of the hash from the previous block, the transactions in the previous block, as well as the nonce (random number). These three pieces of information collectively, along with a random target number, solve the puzzle in order to move onto the next block.
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#4597

  1. Why is it important that the blocks are cryptographically linked together?
    -> For security and integrity of the blockchain, also to avoid double spending.

  2. What does the block structure look like in bitcoin?
    -> The block is uniquely minted through the hash and nounce structure which subsequently will be used to encrypt the next block.

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#4598

  1. Why is it important that the blocks are cryptographically linked together?
    -> For the integrity and security of the block, also it limits double spending and duplicates in the chain.

  2. What does the block structure look like in bitcoin?
    -> A block consists of transactions, a hash (based of the hash of a previous block) and a nonce to calculate the new hash for the next block in the link.

#4599

1. Why is it important that the blocks are cryptographically linked together?
a. To ensure previous block transactions are not changed.

2. What does the block structure look like in bitcoin?
a. Block#
b. Nonce
c. Current Block Transactions
d. Previous Hash
e. Current Block Hash(b,c,d).

#4600

  1. Why is it important that the blocks are cryptographically linked together?

    1. So the previous transactions in prior blocks cannot be changed.

  2. What does the block structure look like in bitcoin?

    1. Block#, nonce, coinbase, transaction detail, previous hash, current hash
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#4601

  1. It is important that blocks in a blockchain are connected through cryptographic links. This is what keeps everything safe and immutable. Each block has a unique digital fingerprint, created from what’s inside that block and the fingerprint of the block before it. So, if someone tries to mess with anything in a block, it messes up that fingerprint, and not just for that block, but for all the ones that come after it. This will result in immediate detection by the other nodes on the network and it will be rejected.

  2. The block structure is as follows:
    a. block #
    b. nonce
    c. current block transactions
    d. previous hash
    e. current block hash

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