Homework on Blockchain and Mining Visually - Questions

Blockchain and Bitcoin 101
#4038

  1. It is important that the blocks are cryptographically liked together because it helps to keep data in the blocks immutable. Make the network fair and honest.

  2. the block structure look like in bitcoin:

    • Hash of the previous block
    • List data of transactions
    • Nonce
1 Like
#4039

  1. If someone tries to change a previous TX the integrity of that blockchain is destroyed.

  2. list of TX, previous Has, nonce, new hash

1 Like
#4040

  1. In order to create a secure network ie you cant double spend and its almost impossible to change history

  2. The previous has, transaction list, nonce which has to be guessed

1 Like
#4041
  1. To keep the integrity of the data accurate and immutable.
  2. Each block contains the nonce that was within the target, the TX list and hash of previous and its own block.
1 Like
#4042

1.) It is important for linking data of transactions and also to avoid double-spending
2.) Block, Nonce, Data, Previous Hash, Hash of the current block

1 Like
#4043

  1. Cryptographic linking of blocks defines the sequencing of the blocks in the chain, and ensures that any attempt to modify transactions in any previously confirmed block in the chain will be immediately evident mathematically as the chain of links will have been broken all the way back to the corrupted block. Miners in the network will therefore act through consensus to ignore the corrupted chain. This gives the block chain immutability.

  2. Each block in the chain is identified by a unique hash based on three elements: a) the root hash of the transactions in the block itself, b) the block hash identifier of the previous block in the chain, and c) the nonce that solved the cryptographic puzzle for determining the current block’s unique hash number.

1 Like
#4044

1 For the security and integrity of the blockchain, to insure no double spending of UTXOs
2 list of UTXOs to fill the block +previous hash solve nonce get the fees +block reward

1 Like
#4045
  1. Why is it important that the blocks are cryptographically linked together?

It makes it Immutable. If it is not linked together then any blocks can be changed or altered and there wont be security.

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

Transaction List
Previous Hash
Nonce

1 Like
#4046

so that everyone can verify ,and new block have details of previous block.
2. transection
input
hash
previous hash
nonce

1 Like
#4047
  1. Linking the blocks in the chain helps to create immutability, as the slightest change to any block will completely break the link, and therefore the chain
  2. Structure of a block:

  • Block Size

  • Block Header containing several fields; Nonce, Difficulty Target, Version, Previous Block Hash, Merkle Root, and Timestamp

  • Transaction counter

  • Transactions

1 Like
#4048

1 to secure the network and to not double spend

2 the hash of the block is based on the previous hash in block+ transactions +random number nonce to to be guessed

1 Like
#4049
  1. Why is it important that the blocks are cryptographically linked together?
    So no one can go back an alter any transaction in previous blocks this add security to the chain. verify not trust
  2. What does the block structure look like in bitcoin? each block has a block number, nonce, transaction data and hash from previous block this generates a unique hash for this block. This starts the next block to use and follows the same rule allover.
1 Like
#4050

  1. So that changing data in one block means changing data in all the previous ones

  2. Previous hash, Data, Nonce, Hash of the new block

1 Like
#4051
  1. It is important that the blocks are cryptographically linked so that nobody can change transactions. This insures the integrity of the block chain. If a transaction is changed, all blocks subsequent to the change will be removed from the blockchain.
  2. Each block has a hash, or a digital fingerprint, which is based on the transactions in the block, the hash of the previous block, and a nonce, which is a random number.
1 Like
#4052

Q.1.Why is it important that the blocks are cryptographically linked together?
A.1.Makes sure that rules are followed, there is no central authority, 3rd party intefere
with the double spending, there is nobody to trust

Q.2.What does the block structure look like in bitcoin?
A.2 blocks made up of = links + current hash = current transaction + previous hash + current nonce

1 Like
#4053
  1. Why is it important that the blocks are cryptographically linked together?

Blocks are cryptographically linked to ensure the security of blockchain. Any one block cannot be altered without having to alter all blocks mined from that point, which is almost impossible.

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

The header, which is a hash of the current block, (includes block transactions, nonce and previous block header hash). List of transactions incorporated into the block, which also include the block reward and fee payment to the miner.

1 Like
#4054
  1. Why is it important that the blocks are cryptographically linked together?

Math and physics ensure the data on the network making sure everyone follows the rules and by cryptographically linking each block together this ensures the integrity of the data on each block including the previous block and the subsequent blocks to follow because as soon as data is changed in one block within the chain, it will result in the chain and links being broken rendering the blockchain invalid.

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

Each block has a unique hash fingerprint which contains the list of the block’s transactions and the nonce that has to be guessed, including the previous blocks hash.

1 Like
#4055

1.Cause it makes the data immutable, very hard to tamper with.

2.Block, Nonce, TXN Data, Previous Hash and Current Hash

1 Like
#4056
  1. It is important that blocks are cryptographically linked because it prevents data from being changed.
    2.The block structure is made from the nonce, data, and previous blocks hash in order to get the current blocks hash.
1 Like
#4057

Homework on Blockchain and Mining Visually - Questions

  1. Why is it important that the blocks are cryptographically linked together?
  • For security and integrity of the blockchain. if not linked together, all previous blocks could be changed. Transactions could be reversed.
  1. What does the block structure look like in bitcoin? Block-Hash = pre-hash, Data(transaction table) and nounce.
1 Like