Homework on Blockchain and Mining Visually - Questions

Blockchain and Bitcoin 101
#404
  1. Why is it important that the blocks are cryptographically linked together?
    The links between blocks are a mathematical puzzle that carry information from the previous block. This adds security to the blockchain, so that no changes can be made to the block.
  2. What does the block structure look like in bitcoin?
    Previous hash, transaction List and nonce
    NONCE- finds the new hash so that the block is accepted by the network and appended to the blockchain
1 Like
#405

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

To preserve : IMMUTABILITY , security

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

HASHING numbers of new block + previous one, NONCE, inputs, txos, halving, block rewards, transaction fees

#406

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

  2. What does the block structure look like in bitcoin?
    Hash
    Transactions
    Pre Hash
    Nonce

1 Like
#407

1. Why is it important that the blocks are cryptographically linked together?
Because it makes it almost impossible to change the information within the blocks.
If information is changed the links will be broken.

2. What does the block structure look like in bitcoin?
A bitcoin block contains
The hash of the previous block.
Transaction information
And a Nonce
These three informations are then hashed using sha-256 to create the blocks own hash.

1 Like
#408

  1. Why is it important that the blocks are cryptographically linked together?
    A. The hash of the current block includes the hash of the previous block. It provides for security of the blockchain so that no previous blocks can be changed.

  2. What does the block structure look like in bitcoin?
    A. Transactions, inputs, outputs, Hash of previous block and nonce.

1 Like
#409

If the blocks are crptographically linked to the previous and also the next block it prohibits the changing of blocks therefore adding to the security and immutablility
2. Block size, block header, transaction counter, transaction, nonce, previous block hash

#410
  1. Prior block hash is used to create new block hash. This linkage prevents any changes to prior block transactions thus making the chain unchangeable or immutable.
  2. A block contains a block header, the hash of the prior block, the transaction data for the new block, the nonce that solved the block.
1 Like
#411
  1. It is important that the blocks are linked together to increaese the security of the blockchain.
  2. Each block contains transactions, a unique address, and some characteristics of the previous block.
1 Like
#412

  1. Why is it important that the blocks are cryptographically linked together?
    Because each block is protected and reinforced by the chain. If someone tries to change a block they must change every block after that particular block as well.

  2. What does the block structure look like in bitcoin? It looks like a chain, thus the term BlockChain. Each block is connected, and the block is hashed using the previous hash (thus linking the chain) + the transactions + the nonce.

1 Like
#413

No previous transactions can be changed because it would break the link in the blockchain.

Previous Hash
Transactions
Nonce

1 Like
#414

Why is it important that the blocks are cryptographically linked together?
A: To prevent that someone changes the blocks.

What does the block structure look like in bitcoin?
A: It contains the hash of the previous block, the coinbase, the inputs and outputs, the nonce

1 Like
#415
  1. In order to ensure that no rules are broken and no data is altered from the previous blocks.
  2. Hash from the previous block, list of transactions, a nonce and the hash of the current block.
1 Like
#416

  1. By linking the blocks together it becomes nearly impossible to change transactions in previous blocks
    -> prevents double spending

  2. Header
    Blocksize
    Blockheader
    Transactionsamount
    Transactions

#417
  1. Because it ensures Blockchain Integrity. In fact, by cryptographically linking every block to its previous ones, then any change that someone could attempt to make to a block in the Blockchain would force that someone to accordingly change every following block. By using hashing functions, in which for any given input there is only a specific unique output, this process is strengthened as any change in a block that has previously been hashed would produce a different hash for the modified block, making it impossible to simply change it without affecting the entire chain.
  2. Every Block in the Bitcoin blockchain is composed of a header and a list of transactions. The header contains information about the previous block’s hash, the timestamp, the nonce and other. The list of transactions shows inputs (previous UTXOs) and outputs (new UTXOs). Outputs UTXOs can be distinguished between those actually assigned to a third person, those returned to the sender and transaction fees rewarded to miners.
1 Like
#418

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

System Security, Transparency, Integrity. Change 1 hash and it changes all the previous hash.

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

It contains a transaction * TX*
Hash From Previous Block.
Nounce

1 Like
#419

  1. Blocks being cryptographically linked secures the network, the cryptographic link is made by miners and is the PoW.

  2. Each Bitcoin block consists of the data on the current block, the hash of the previous block, and a nonce.

1 Like
#420

  1. The ultimate reason is one of security. If even one bit of information is changed in any previous blocks the network becomes instantly aware someone has tampered with previous information.

BLOCK HEADER
VERSION
PREVIOUS BLOCK HASH
HASHED MERKEL ROOT
TIMESTAMP
BLOCK SIZE
TARGET DIFFICULTY
NONCE
EXTRA NONCE
TRANSACTION COUNT
TRANSACTION
COINBASE TRANSACTION

1 Like
#421
  1. To secure the network
  2. Block#,nonce, data, previous hash,new hash.
1 Like
#422

1 - with the previois block’s hash in the current block’s has - the “blockchain” retains integrity of the leger (database entries)
2 - the transactions in the block (data)

  • the nonce + the hash of the previous block = the current hash (the BTC)
1 Like
#423
  • Why is it important that the blocks are cryptographically linked together?
    they link between together, mathematical and proof of work.
  • What does the block structure look like in bitcoin?
    block, nonce, transaction, hash
    [/quote]
1 Like