Homework on Blockchain and Mining Visually - Questions

Blockchain and Bitcoin 101
#2955

  1. Ensures blocks remain immutable

  2. Hash of previous block, transaction of current block, nonce

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#2956
  1. Why is it important that the blocks are cryptographically linked together?

The cryptographic link ensures that no data in the blockchain is modified after the block has been created. The validity of the currency depends on all blocks conforming to this immutability.

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

Genesis block has no previous hash linked; every subsequent block links itself to the previous block with the hash ID of the previous block included in its own hash. In this way it looks like a strand of beads if it were mapped out fully.

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#2957

  1. It’s important that the blocks are cryptographically linked so that altering previous blocks is so costly that it becomes virtually impossible. This ensures that the network is secure.

  2. The block structure is as follows:

  • Magic number (0xD9B4BEF9)
  • Block size
  • Block header:
    a) Version
    b) Previous block’s hash
    c) Transaction list hash
    d) Time
    e) Target
    f) Nonce
  • Transaction counter
  • Transactions
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#2958

  1. So past, present, and future blocks remain immutable.

  2. Each block has a hash or digital fingerprint. It is based on the previous hash, the transaction list, and random numbers or a nonce.

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#2959

  1. It prevents the information from being changed. Creating Data immutability. Like carving on a stone. Preventing the ability to double spend.

  2. The block structure contains the hash, transaction fee list, the nonce and the previous hash creating consensus and immutability.

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#2960
  1. Blocks are cryptographically linked together is very important because doing so you cannot change previous data due to hashes and it secures the network
  2. Block structure looks like in bitcoin because it is linked to previous block hash, adding transaction hash and guessing nonce.
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#2961

  1. Blocks are cryptographically linked together to prevent data from getting changed and to make date hard to change.

  2. A Block contains hash of previous block, list of transactions and nonce.

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#2962
  1. Why is it important that the blocks are cryptographically linked together?

to keep the blockchain immutable therefore prevents double spend

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

hash=(prev hash+tx list+nonce)

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#2963
  1. Cryptographically linking the blocks together secures the network by rendering the chain unbreakable if any bit of information is changed.
  2. Block #, Nonce, Data, Previous hash, Hash
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#2964
  1. It’s important, so that it’s extremely difficult to alter history.
  2. Te structure consists of the previous hash, the current transactions, and a random number called nounce.
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#2965

  1. It is important that the blocks are cryptographically linked together so that it secures the trustless network and everything can be traced back to the source to be verified.

  2. Each bitcoin block is a hash of the previous hash, the transactions (TX) and the nounce.

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#2966
  1. Cryptographic interlink between the blocks of a blockchain ensures security and immutability of the network. Cryptotechnology lying in the foundation of a blockchain protocol makes it impossible for anyone to interfere within any of the blocks on the network without experiencing both - huge technical challenge and substantial economical loss.
  2. Block Structure: Block Hash (header) - Previous block hash - Transactions of the block - nonce.
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#2967

  1. It is important for the blockchain to be linked cryptographically so that miners cannot double-spend and it also ensures integrity and immutable.

  2. The structure of any block contains a nonce, the transaction list, and the previous hash.

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#2968

  1. to secure the network and make the blockchain more reliable.

  2. It is the previous block hash, current block data hash + nonce.

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#2969

  1. Why is it important that the blocks are cryptographically linked together?
    So that if a miner goes back and changes the transaction in a previous block that will invalidate all subsequent hashes. In order to make the fraudulent hashes permanent the miner would have to vastly exceed the collective hash rate for as long as it took to catch up with the rest of the network’s block creation. The fraudulent miner’s task would grow exponentially higher for each block it was behind the rest of the network.

  2. What does the block structure look like in bitcoin?
    The block structure includes:
    -a header which contains info such as the Bitcoin version number, the previous block hash, Merkle root, block timestamp, and difficulty target
    -Transactions
    -And a hash of the above data that meets the difficulty target

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#2970
  1. Why is it important that the blocks are cryptographically linked together?
    fo security
  2. What does the block structure look like in bitcoin?
    prev hash, trans, nonce,data & current block
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#2971
  • Why is it important that the blocks are cryptographically linked together?

The linkage will prevent Someone from attempting to alter a previous block. As soon as something is changed it will sever all the following blocks. So this provides security.

  • What does the block structure look like in bitcoin?

It starts with a Header containing all of the meta data:

Previous Block Hash, Merkle Tree Root: transactions (as many as 500)

Time stamp, nonce and target

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#2972

  1. Why is it important that the blocks are cryptographically linked together?
    This stops someone from altering a previous block in the block chain, as any change to a block will affect the hash value for all the following blocks.

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

    • Block number
    • Nonce
    • data in the block
    • Previous hash value
    • Current block hash value
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#2973
  1. It prevents change in the previous blocks
  2. a hash is calculated based on previous hash, data in the current block and a random nonce.
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#2974
  • Why is it important that the blocks are cryptographically linked together?
    -To make the whole system more secure and difficult to break in…
  • What does the block structure look like in bitcoin?
    -Prev Hash, Txs list, nonce number.
1 Like