Homework on Blockchain and Mining Visually - Questions

Blockchain and Bitcoin 101
#1567
  1. Why is it important that the blocks are cryptographically linked together?

To make it improbable that someone can delete an old block.
2. What does the block structure look like in bitcoin?

It looks like an email

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#1568

  1. This provides a way of verifying no previous blocks have been altered. Since any alteration would change the blocks hash functions and all other blocks hash functions rely on the previous block it would result in the entire chain being broken.

  2. Block Hash function = Nonce, Data (transactions), and previous block hash function

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#1569

  1. Why is it important that the blocks are cryptographically linked together?
    By linking blocks it creates an inimitable history of the ledger. This is a fundamental of the BTC protocol as it only tracks the movement of BTC on a network.

  2. What does the block structure look like in bitcoin?
    Past bock hash+ current transactions of new block X a nonce< target = a new Block

Why doesnā€™t the BTC protocol just track the variance in the past block and the new block?

Something like this (Block New- Block Old) x nonce < target = New block?

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#1570

  1. To make the whole chain secure and interlinked. In this way, it will be challenging to edit the confirmed block as it will affect all the blocks after.

  2. The block will contains the block header, previous hash value, transactions to be confirmed and nonce

2 Likes
#1571

In what regard does it resemble an email? :stuck_out_tongue:

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#1572

Yes, but you donā€™t use the new block hash to get the new block hash since you donā€™t know that value yet :stuck_out_tongue:

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#1573

  1. Is important due the integriy of the blockchain. Links are based on information of previos blocks, if that info changed, links will be broken affecting the integrity of structure and conections will be invalid.

  2. Structure block : previous hash, transaction list ( of current block), nonce , current hash.

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#1574

  1. This maintains the integrity of the blockchain by insuring no double spending or other false transactions happen and also so that no previous transactions can be changed.

  2. Contains the list of transactions, previously mined blocks and their hash, and the nonce which is the number used to get the hash rate low enough to be accepted.

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#1575

1.security measures.so no one can alter data
2.its present and previous hash plus nonce

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#1576

  1. It is important that the blocks are cryptographically linked together to ensure the integrity of the chain. If one is altered, then all that follow must be altered as well.

  2. The block structure contains the previous block hash, transactions list and the nonce number

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#1577

1. Why is it important that the blocks are cryptographically linked together?
the link between all the block is a security measure so that nobody can go and change any prior transactions as each block is linked by a mathematical equation it is almost impossible to change
2. What does the block structure look like in bitcoin?
1:Block number
2:Nonce
3:Transaction Data
4:Hash of the Previous Block
5:Hash of current block

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#1578
  1. this way you creat a chain. you cannot change anything in a previous block without a impact on the following. it is practically impossible to change a old block and catch up with the new attached block. it is about safety. also you earn more money to mine with a 51% of conputer power than to change or double spend any amount. you have no incentive to do that.
  2. block hash, tx list, nonce, hash of previous block
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#1579

  1. The reason that it is important that the blocks are cryptographically linked together, is because it makes it pretty much impossible to make changes or alter any block, because all the blocks are linked together. If you change 1 block, all blocks after that block will have a changed hash.

  2. The block structure of bitcoin is as follows. Each block contains transactions, a hash, and a nonce. The hash is created from the transactions of the current block, the hash of the last block, and nonce, which is a random number generated by miners. When these 3 things are hashed together you must get a hash that is lower than the target number, once this happens the current block gets the hash. The target number decreases as mining difficulty increases

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#1580

1.) It is important that blocks are cryptographically linked together via the Hash because each block contains information from the previous block and any change to any block transaction breaks the link.

3.) The block structure is a set of ever increasing data structures encrypted into separate blocks of transactions and each block is linked by a hash. Through the hash connecting all blocks information is passed which is immutable to the blocks and no information of one block can be altered with out breaking the block links and invalidating all blocks simultaneously.

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#1581

this makes the blockchain secureā€¦no previous changes are possibleā€¦no double spending

they are somehow all connected together because of the hash from the block before and the transactions what makes a special hash connection the links thrue the whole blockchain

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#1582

1.- It is important because it is what causes that in case a block through a transaction is changed, all following blocks are changed, this gives the security to the blockchain.
In the current block, we have the hash of the previous block and transactions, and in the next will have the current hash of the block and transactions and so on. everything is linked.

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#1583

  1. Why is it important that the blocks are cryptographically linked together?
    This is what makes them secure, so the data canā€™t be change in the future.

  2. What does the block structure look like in bitcoin?
    It contains the block number, the transaction data, the hash of the previous block, the hash of the current block and the nonce.

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#1584

blocks are harder to alter

header - previous block hash, time, nonce, current target

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#1585

It is important that the blocks are cryptographically linked together because thatā€™s what makes a blockchain, a blockchain. Each transaction block has to be connected in order to increase the trustlessness of the system. It ensures accuracy in each block because if something is inaccurate, each block after the inaccurate one will be corrupted as well. All the hashes will change and every node can notice. It also allows for the process of mining because without the previous blockā€™s hash as part of the mining process, the equation is ā€œcurrent blockā€™s transactions + nonce = current hashā€ instead of ā€œprevious hash + current blockā€™s transactions + nonce = current hashā€, making it much easier to guess the nonce and impeding on the incentivization of the entire process.

The block structure in Bitcoin looks like:

Block Header

Previous Block Header Hash

Merkle Root/This Blockā€™s Transactions

Each block is connected by the previous blockā€™s hash, forming the blockchain.

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#1586

  1. That helps preserve the integrity of ledger and prevents alterations to it because, if a change is made to a block all the subsequent blocs in the chain have to be mined again.This property exists precisely because the blocks are cryptographically linked together.

  2. The structure of a block on the chain is as follows:

    • List of transactions
    • hash of the previous block
    • nonce
    • hash of the current block which is a hash of all of the above.
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