Homework on Blockchain and Mining Visually - Questions

Blockchain and Bitcoin 101
#2452

  1. Why is it important that the blocks are cryptographically linked together?
    The link between the blocks is a mathematical puzzle that links all previous blocks together.

  2. What does the block structure look like in bitcoin?
    The block structure is all built on top of each other. Where one block is connected to all blocks below and all future blocks above. It shows the previous block hash, current tx’s/data, and nonce…

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#2453

  1. The current block’s hash is based on the current transactions and the previous hash. If you try to change the data from a previous hash, you would need to re-mine all of the blocks moving forward. It is important that the blocks are cryptographically linked together so that the previous transaction data cannot be changed.

  2. Block structure = transaction data + the previous hash + the newest guessed nonce

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#2454
  1. To ensure the fact of integrity on previous and future hash chains. Making a unique fingerprint across the blockchain.
  2. Each block linked with a TX hash of the previous block and the nonce number and the inputs and outputs moving forward. all getting hashed again to the next block with the previous hash and nonce.
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#2455

Homework on Blockchain and Mining Visually - Answers

  1. Why is it important that the blocks are cryptographically linked together?
    • To prevent a malicious actor(s) from trying to alter or delete a previous transaction. If something gets changed in a block, the hash changes for that block plus the hash for all blocks that follow. Thus the link is broken.

  2. What does the block structure look like in bitcoin?
    • Hash of previous block + transaction list for current block + nonce
    • Block # + Nonce + Data (transactions) + Previous block hash + Current block hash

blockchain.Ronin

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#2456

Why is it important that the blocks are cryptographically linked together?
Because this ensures the integrity of the all blocks throughout the entire chain. This is wat makes sure the rest of the chain is completely invalidated if a block is altered.

What does the block structure look like in bitcoin?

  1. Data (the transactions in the block)
  2. Previous block hash
  3. Nonce
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#2457

It’s very important because when miners resolve the puzzle, it creates a special link that has a connection with the previous link and so on. So, if one special link is broken, all the previous links will be broken and would take thousands of years trying to fix them.

a block based on:

  • Nonce (random number)
  • list of transactions
  • previous transactions.
  • a Hash obtained for that block.
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#2458
  1. Why is it important that the blocks are cryptographically linked together?

Its important the blocks in the blockchain are linked together using cryptography because that is what makes the blockchain immutable and secure. Without the cryptographic link to the previous blocks, it would be possible for malicious nodes to modify transactions without detection.

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

The block structure of bitcoin contains three primary components: previous block’s hash, a list of transactions in the block and the nonce.

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#2459

1.Cryptography linking of blocks blocks ensures that if a previous block is changed the entire chain from that point is broken on the node where the change is made. This will separate that node from other nodes to maintain the integrity of the blockchain.
2. A collection of continuous linked blocks of data in SHA256 form

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#2460

1: they have to be cryptographically linked together so that if one block is changed then the links to the other blocks are automatically broken. The “cryptographically” is there to make it impossible to reproduce fast enough.

2: the block contains the hash of the previous block + the hash of the current transaction + the nonce that makes the new hash fit under the boundaries of the target.

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#2461

The Blockchain is a continuous of hashes, any subtle manipulation will alter the subsequent blocks making obvious that something is wrong.

It has two main section. A section where all the transactions are stored, and a second section consisting of a header that contains the nonce, the hash of the previous block, the hash of the current block and maybe the date.

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#2462
  1. This is to ensure integrity of the information in the block chain. Any attempt to change a block (eg to erase a transaction, double spend etc) will break the link with the next block which would have to be changed, breaking its link with its next block etc.
  2. Each block contains the hash from the previous block, the encrypted list of transactions in that block, and the nonce which has been successfully guessed to produce a hash function for the block which is below the target value which was set for that block.
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#2463
  1. to ensure security, noone is able to go back and change previous blockchain without affecting and changing all others making it impossible to do so.
  2. there is a hash that represents the block of all transactions, the hash is unique bashes on that specific block
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#2464

  1. Why is it important that the blocks are cryptographically linked together?
    The blocks being linked is part of the security structure. It means that any attempted change effects those linking forward from the effected block - creating a exponentially higher amount of work and money needed to change not only the intended block but everything that follows.

  2. What does the block structure look like in bitcoin?
    The block contains the transaction data, the previous hash, and the nonce that the miner is attempting to find.

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#2465
  1. this makes the chain more secure. And therefor it is more difficult to change input in previous blocks.
  2. the ‘block’ consists of TX inputs and outputs, with a hash and nonce
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#2466

By cryptographically linking the blocks, it creates a blockchain where nothing from a previous block can be changed. It provides integrity to the chain.

The block structure looks like a chain of blocks, each built upon the hash of previous blocks.

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#2467
  1. The links ensures security and incorruptibility
  2. Blocks are linked chronologically, each block has a hash composed of the transaction, the hash of the previous block and the ‘nonce’. Every accepted block has achieved a hash below the target.
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#2468

  1. Why is it important that the blocks are cryptographically linked together?
    a. Maintain history - to change a bit of history you need to change the entire block chain which is practically very difficult task to achieve.

  2. What does the block structure look like in bitcoin?
    1 Block1 - No Input its hash will be the hash of Nonce + number of transactions.
    2. Block2 - hash of (Block1 Hash -> Current transactions + Nonce)
    .

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#2469
  1. Why is it important that the blocks are cryptographically linked together?
    This ensures security. To alter any transaction in the link would destroy the entire chain.
  2. What does the block structure look like in bitcoin?
    It consists of the previous block’s hash, the transaction data and a random nounce; the product of these numbers if below a certain threshold will be the previous hash for the next block.
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#2470

  1. It is important that the blocks are cryptographically linked in because only that way you can make sure that there cannot be a historical change in previous blocks/transactions.

  2. Block is structured from previous blocks hash, local mempool (more exact the list of transactions from mempool that would fit in upcoming block), and the appropriate nounce.

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#2471
  1. Why is it important that the blocks are cryptographically linked together?
  2. Blocks are cryptographically linked so hashing can take place(Digital footprint). A block is consists of the previous hashing, the transaction of the current block, and hashing of the current block. The current block need to do guessing to arrive at a solution for that block.
  3. What does the block structure look like in bitcoin?
  4. It locked like a cascade windows with text boxes that contains the previous hash values in hexadecimal/binary form, it has the transaction/s for the current block , the hashing text box for the currently block and a text box that displays the amount of transaction. Each block in the cascade contains the hash value of the previous hash.
    [/quote]
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