Homework on Blockchain and Mining Visually - Questions

Blockchain and Bitcoin 101
#424
  1. It is important that the blocks are linked together to ensure the security/integrity of the network. If you change one block, you must then change all the later blocks and create new tased links between them, which is practically impossible.
  2. The block structure in bitcoin is made up of a)the transactions in the block, b) the hash of the previous block and c) the nonce.
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#425

  1. Linking the blocks cryptographically makes them immutable because if if you alter any data in the block it changes the hash of that block which will then break the chain of the subsequent blocks

  2. a) The hash of the previous block
    b) Timestamp
    c) A hash of all the transactions in the current block
    d) Nonce
    e) Transactions

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#426

  1. Why is it important that the blocks are cryptographically linked together?
    Blocks are cryptographically linked together to maintain integrity of data from modification. It makes data in blockchain secure of modification.

  2. What does the block structure look like in bitcoin?
    Block structure which are made up of previous hash plus transaction looks like blocks of data link together but in mathematically hashed form.

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#427

  1. It is important that the blocks are linked together so that they cannot be altered after ,without the alteration of all previous blocks.

  2. The block structure contains the hash of the previous block ,the current transaction in the block and the nonce to be mined.

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#428

There is more information. You have time, nonce, all transactions saying where the btc is going, target, previous blockhash,ā€¦ Ect
all this information will produce a blockhash for this certain block of transactions.

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#429
  1. Helps to keep miners honest and data being altered
  2. previous previous mined hash, tx list and nonce (random number to be guessed to have block accepted
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#430
  1. It is important to be cryptographically linked in order to avoid tampering. As we mentioned before, you change 1 block and that would affect the previous block, and so forth.
  2. You would see: hash of each block, previous hash, nonce.
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#431

[quote=ā€œivan, post:1, topic:8433, full:trueā€]
Homework on Blockchain and Mining Visually - Questions

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

Essentially to protect data, safe guard transactions, and secure the whole integrity of the Bitcoin blockchain network.

If someone goes back to a mined block and tries to change any single data from the block transaction, all the following chained blockā€™s hash will be changed as well as the hash of the tampered block. That is because each mined block apart from genesis/first block is cryptographically interlinked to the previous and the following blockā€™s hash. This makes it more difficult to change a block. When you change one block, you have to change all the blocks and create new hashed relations between the blocks, which is virtually impossible and not been done as of yet.

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

++++++++++++ Inside a Bitcoin Block Structure ++++++++++++

  • Version - Describes the structure of the data inside the block. This is used so that computers can read the contents of each block correctly.

  • Block Header/Name - data about the block.

  • Current block hash - All of the transactions inside the block hashed together to form a single line of text. All of the fields are unique, this is the most significant part of the block header.

  • Previous Block hash - An identification number for the previous block.

  • Timestamp ā€“ helpful to have

  • Block Size ā€“ size of the data in the block

  • Difficulty Target - A value that miners work with to try and add candidate block to the blockchain. It is set by the bitcoin network, and will make more sense in a moment.

  • Nonce varying random number that must be below the target.

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#432
  1. immutability man cant change one without changing the other.
  2. transaction data, mining difficulty and nonce
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#433

yes indeedā€¦of course ā€¦thanks

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#434
  1. Itā€™s important that the blocks are cryptographically linked together so that a change to a block will also changes the link. This secures the blockchain.
  2. Bitcoinā€™s block structure has the previous block hash, the transactions and the nonce.
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#435

  1. It is important for blocks to be cryptographically linked to each other, because then you cannot change any information on one block without having to change the information on all other blocks that follow. This makes it nearly impossible for anyone to alter the network. In other words, it gives it immutability.

  2. The block structure of bitcoin consists of the previous block hash + all of the transaction data for the block currently being mined + the nonce found by the miner. These things are combined to give us the hash of the next block.

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#436

it is important that blocks are linked together because each previous ā€œlinkā€ is the hash of the previous block and the nonce that was linked to solving the puzzle.
The block structure of bitcoin is the following: H(k|x)=Y
H=Hash
k= Nonce
| = connecting to the two together (basically a + function)
x= The hash of the block
Y= The difficulty target
The block must consist of the previous hash, transactions list or data, and nonce. The block is then hashed to see if it is lower than the target difficulty and if so, is accepted onto the chain.

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#437
  1. Why is it important that the blocks are cryptographically linked together?

So that the alteration of one would alter the content of the following blocks

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

It contains:

1-Number of the block
2-Hash of the block
3-Hash of the previous block
4-Nonce
5-Transaction list

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#438

  1. It ensures the integrity of the network. Any alteration of a previous block affects the hashes of all ensuing blocks, making fraud incredibly difficult.

  2. It is made up of blocks of transactions, linked by the solved cryptographic puzzle, which is comprised of the hash of the previous TXs and the nonce.

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#439
  1. Tampering with one block will require re-mining each subsequent block which would require too much time and energy.
  2. It has the previous hash, the current hash, nonce, transaction.
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#440
  1. Why is it important that the blocks are cryptographically linked together?
    thatā€™s what make the blockchain immutable
  2. What does the block structure look like in bitcoin?
    it has hash of previous block, transaction, nonce, hash of current block
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#441

  1. It is important that the blocks are cryptographically linked together because this ensures the security of the network. It prevents bad actors from altering transactions because they would not have the computing power required to mine the altered block and every following one, which would be necessary because each block is linked cryptographically. When a transaction within a block is changed, the hash of that block and every block after it is changed, too.

  2. The block structure of Bitcoin is composed of the hash of the previous block, the data within the current one, and a nonce which has to be guessed by the miner. Only if the hash of the sum of this data falls below the target threshold will the block become valid and accepted by the network.

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#442

  1. Security ā€¦ones you alter a block the hash is changed and you will have to alter all the blocks. By keeping them linked they insure the integrity ofnthe network.

  2. Previous hash,transaction fee ,current hash

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#443

1.Block are cryptographically linked together so that a change in one block necessitates changing all subsequent blocks.
2. Previous has, transactions, and nonce.

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