Homework on Blockchain and Mining Visually - Questions

Blockchain and Bitcoin 101
#4302

Why is it important that the blocks are cryptographically linked together?
To ensure the blockchain is security,nobody can modify previous transaction in the block and break the link between block to make blcokchain invalid.
What does the block structure look like in bitcoin?
Block number + nounce + list of transactions + the previous block hash + hash of current block.

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#4303
  1. Why is it important that the blocks are cryptographically linked together? It provides incentives for miners to play by the rules and be honest otherwise the block will be rejected.
  2. What does the block structure look like in bitcoin?
    Nonce
    Data
    Previous hash
    Hash
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#4304

  1. It’s important that they are cryptographically linked because its adds a higher level of security and immutability.

  2. Current Block Hash, previous block hash, transactions, nonce

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#4305

  1. because when one block is corrupt the links in the chain previous become corrupt defeating the principle of incentive: profit/money

  2. nonce # + transaction list (data) + previous hash # = new unique hash #

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#4306

  1. The links are important to maintain integrity of the data and achieve trustlessness

  2. A block consist of a nounce, data/transactions and the hash of the previous block

2 Likes
#4307

Homework on Blockchain and Mining Visually - Questions

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

With the blocks being cryptographically linked, the puzzle becomes harder over time while staying self regulated. This creates more security because the new puzzles build off of the previous puzzles/hashes and there must be consensus when a new block is formed by verifying previous hashes.

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

SHA256[(Prev. Hash) + (New Transactions) + (Nonce)] = [(New Hash) < Target Number]

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#4308
  1. Why is it important that the blocks are cryptographically linked together?
  • so that it’s practically impossible to tamper the database – which means very high security
  1. What does the block structure look like in bitcoin?
  • nonce
  • tx list
  • previous hash
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#4309

1.To secure the block chain or ledger, Preventing someone from changing transactions in the past
2.The current block Is based off of transactions in the block and the previous block hash ID

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#4310
  1. Why is it important that the blocks are cryptographically linked together?
  • This for security resons.
    When you change a block in the past, all links after this block are broken and you have to start mining these blocks again. Because the difficulty of mining is so high, you need so much mining equipment that it is to expensive. In addition, the longest blockchain is seen as truth. So you also have to be able to mine the old blocks very quickly to get the longest chain. In theory you should get 51% of the hash capacity to get this done.
  1. What does the block structure look like in bitcoin?
  • Block number
  • Nonce
  • Transaction Data
  • Hash of the Previous Block
  • Hash of current block
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#4311
  1. To maintain the integrity of the blockchain and make it almost impossible to change
  2. Block structure = previous hash, transaction link, nonce to then find the current hash of block that is lower than the target
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#4312

  1. To prevent previous blocks from being altered by having to re-validate every chain between each block.

  2. The block structure has the previous block’s hash, the present block’s inputs / outputs and transactions, the present block’s hash, and it’s nonce.

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#4313

  1. To ensure data integrity within the network, to ensure there is no double spending.

  2. Previous Hash
    Tx list
    Nonce

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#4314

Why is it important that the blocks are cryptographically linked together?
its important as it shows the blocks have not been modified

What does the block structure look like in bitcoin?
linked blocks side by side, each block has a block number, nonce, data, prev block hash and current block hash

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#4315
  1. To make sure that all the miner follow the rule and can’t alter the history.
  2. Nounce, data, previous hash, hash
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#4316

  1. by connecting and linking blocks,they transfer data and keep a level of security inside the blockchain.

  2. hashes are connecting block that contains data,then makink their own hash based on the previus one and linking it to another block.

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#4317
  1. The linkage of the the blocks ensures the integrity of the chain and rules out the possibility of tampering or violating the blockchain protocol. The fact that each block requires to a) hash the previous block hash and b) to hash its own transactions and c) determine its own nonce according to the particular target required at the particular time in which the block is being created and validated, ensure that it is impossible to make any changes or to corrupt the chain if one expects the rest of the nodes to validate the block as well as to collect the rewards for mining and for the transaction fees included in the mined block.
  2. The Block is composed of several parts:
    a) The Block Number (So, its position in the chain)
    b) The Nonce, which is the particular number that was required to solve the target hash puzzle for that particular block to be accepted and added to the chain
    c) The Data or transactions included in the block, in other words the sum of all the UTXOs between different wallets and the transaction fees associated to for each of those
    d) The hash of the previous block
    e) The resulting Hash of the new block having applied the Nonce and filled in the Data
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#4318
  1. Why is it important that the blocks are cryptographically linked together?
    To create a chain that is robust and (too) hard to change. It enables putting in a rule that needs a cryptographic puzzle to be solved to create or change a block.
  2. What does the block structure look like in bitcoin?
    Linear
#4319
  1. It ensures the integrity of the data in the blockchain, as a change in one block triggers changes in all the following blocks.
  2. Previous hash (of the previous block), transactions and nonce (number that miners are solving for). The hash of the current block is generated based on these factors.
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#4320

1-it is important to secure the chain. Anything changes in a block will change the hash of the block. the next block has the hash of the previous block; so the next block will be changed as well. it is imposssible to change anything in the “previous” block. That situation makes the link between blocks.
2- there’s a hash which contains nonce a random number which is costly to guess and makes blockchain secure and incentivized, Tx data which is the whole aim to collect, and the hash of the previous block. In order tp regulate mining facilities by number, the more miners work on BTC, the lower the target is, which means the more difficult to make mining. guessing a number will be a valid hash as long as it is between zero and the target. the lower the target is harder to find in the right scale.
other segments are transaction counter, block header, blocksize and the current target

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#4321

  1. The cryptographical link between the blocks , and especially the fact that the hash of a block takes into account the hash of the previous block, is what provides security to the blockchain by making it next to impossible to make a change to a previous block.

  2. in bitcoin, the block structure looks like : block number - nonce - transaction data - hash of the previous block - hash of the current block

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