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blockchain

Tamper Resistant Nature of a Blockchain β›“

✨Tamper Resistance in Blockchain

Hey everyone πŸ‘‹πŸ»,

In this article, let us understand the Tamper Resistant Nature of a Blockchain. This is the third part of my Blockchain Series on Dev.

πŸ“¦ ↔ πŸ“¦ ↔ πŸ“¦ ↔ πŸ“¦ ↔ πŸ“¦ ↔ πŸ“¦

Tamper Resistant Nature of a Blockchain β›“

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Every block πŸ“¦ of the blockchain contains its own hash value and the hash of the previous block (previous block hash) in the blockchain. These hash values chain the blockchain together in order in which the most recent block was made and goes all the way to the very first block that was created.

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Whenever the data of a block gets changed, the hash of the block needs to be re-computed and this invalidates the block.

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Now as a consequence of this (hash of the block changing), it also changes the hash of the block that exists on the next block. This changes the data in that block as well changing the hash value and hence this block will also get invalidated too. This change of hash values will run all the way down to the set of the blocks effectively breaking the entire chain. This proves that blockchain is TAMPER PROOF !

So this is it for the third article on Blockchain. Thanks for reading !

Categories
blockchain

Understanding the Structure of a Block πŸ“¦ in a Blockchain β›“

✨Blockchain Structure

Hey everyone πŸ‘‹πŸ»,

In this article, let us understand the Structure of a Block in a Blockchain. This is the second part of my Blockchain Series.

πŸ“¦ ↔ πŸ“¦ ↔ πŸ“¦ ↔ πŸ“¦ ↔ πŸ“¦ ↔ πŸ“¦

The Structure of a Block in a Blockchain β›“ ?

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Blockchainas we know, is a shared digital ledger that records a list of transactions that happen throughout the network. Now this can pretty quickly become longer thus ending with a never ending list of transactions. To get more fine grain control, it is split into a chain.

Right. A chain of blocks β›“πŸ“¦.

So let us understand what a block πŸ“¦ is:
πŸ“¦ Block is kind of a box into which we group all the transactions that we want to add to the blockchain.

Other than a list of transactions, a block also holds a couple of other things.

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In the header of the block , we have a couple of other things:

πŸ‘‰πŸ»Previous block hash
πŸ‘‰πŸ»Timestamp (the time a black was made)
πŸ‘‰πŸ»Merkle Root
πŸ‘‰πŸ»Nonce

✏ Previous Block Hash

It is the hash value for the block that comes directly before the given block in the chain. This is what helps in connecting the blocks of our blockchain.

Timestamp ⏲✏

It is the time that represents when the block was made. This helps us in knowing when certain transactions took place and also solves other problems which we will discuss a bit later.

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Merkle Root 🌴

It is the hash that represents the entire transactions that happened inside the block.
To find the Merkle Root, pair of transactions within the block are repeatedly hashed together until we are left with a single hash value.

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Nonce

Nonce stands for “number only used once,” which is a number added to a hashed block in a blockchain that, when rehashed, meets the difficulty level restrictions. The nonce is the number that blockchain miners are solving for, in order to receive cryptocurrency. We will learn more on this in a separate article on Bitcoin

So this is it for the second article on Blockchain. Thanks for reading !