Homework

write the definition of blockchain. And how our data blockchain is protected from hackers.? And write in details about Data, Hash and Previous Hash tag and explain through screenshot.

Introduction

The blessedness of crypto and cryptography cannot be overemphasized, taking a peep into the decentralized nature of crypto you will believe that it is worth appreciating.
In this assignment I will be opening your eyes to how secure blockchain is and also about hash tags.

Definition of blockchain

Source
Blockchain can be seen as a digital data that makes use of decentralization and cryptographic hashing in keeping details of a digital asset that is immutable and clear.

Blockchain possesses a ledger where all arithmetic information that has been finalized is shared in a propagate idiosyncrasy to all active nodes, accessible through smartphones and computers, where the system of ambry consist of catalog related via cryptography.

Due to the decentralized nature of blockchain, it is impregnable and crystalline. The high level of security and transparency in blockchain have made it impossible for hackers to carry out hocus-pocus.
Blockchain consists of several vital parts which may include Data, Hash and Previous Hash tags.
Blockchain is easily accessible by anybody via online irrespective of your location without appealing for a go ahead order from a third party.
For instance, in the local bank, if you want to withdraw your fiat currency you will have to queue up, thereby spending a lot of time. Sometimes, you will be subdued to submitting documents and your transaction may not be approved in the absence of the documents, but in blockchain technology there is no such thing.

Blockchain functions as an individual block correlated with other blocks, and acts as a registry folder. These other blocks are also linked with other block making it impossible to change them, because any alteration will lead to changes in the incoming blocks which will take a whole lot of time.

How our data on blockchain is protected from hackers.

Blockchain is a propagate arithmetic register apportioned, renovated, and synchronized to all connected computer network and built upon a server. That is to say, a user's data can only be controlled by him.

Blockchain uses cryptographic hashes to secure data, i.e data entered into a computer cannot be altered. However new data are been recorded while previous ones are still obtainable.
For instance,
In the medical line,using blockchain technology, a patient's medical data can be added into a computer network, that is interrelated to other computers. Log in, Data, information, and transactions made by user is stored and can be updated, and whenever data about the patient is required, it can be be easily retrieved.

Taking cognition of the above reasons, you will get to believe that blockchain technology will be secured from hackers. Any attempt to hack into blockchain will be related to all users.q
Any attempt to change data, will bring about changing the blocks, which are interrelated and interlaced. If the hacker wants to change data in block 2 then block 3 and 4 are changed which is likely impossible because of the time it will take.

Write details about Data, Hash, and Previous Hash tag and explain through screenshots.

Visiting https://andersbrownworth.com/blockchain/blockchain to access Data, Hash, Previous Hash tag

Data

Data in blockchain are stored in every block in the blockchain. In the crypto world, informations about transactions: where money is sent from, how much money is sent, where the money is sent.
It is irreparable to alter the data because the information is available in blocks. Below is the screenshot of what I explained

Hash

The identification number of each block is given by hash. the variation in the unique code of blocks in blockchain explains the importance of hash. And any change in a letter will cause a change in the entire hash.
Below is a pictorial explanation of hash

Previous hash

The decentralized blockchain is made up of previous block and new block. When new data is filled, new block is been created and the hash code of the previous block is inserted into the new block. Changing a block will bring about change in hash and leads to change in previous hash and since the new block is connected to the previous hash, it will be invalidated.

How data, hash and previous hash are important elements of blockchain technology.

Block 1
Nonce. 11319
Data.
Prev. 0000000000000000000000000000000000000000000000000000000000000000
Hashes. 000015783b764259d382017d91a36d206d0600e2cbb3567748f46a33fe9297cf

Block. 2
Nonce. 35230
Data.
Previous. 000015783b764259d382017d91a36d206d0600e2cbb3567748f46a33fe9297cf
Hashes. 000012fa9b916eb9078f8d98a7864e697ae83ed54f5146bd84452cdafd043c19

Taking a close look at the above information we can say that no two blocks have the same nonce, data, hash and previous hash.

Using crypto academy season 4 information, lets see what will happen

The alteration of data brought about invalidation of all blocks giving the previous block no value and changing the hash of the first block to 1eab4e2504ae5e6f49e49f17c409316710151e90d1894b955a7c6baed5f695e1
Let me try changing data in block 3 with the information Crypto academy season 4.

Block 2 remained unchanged, i changed the information of the next block but the nonce, previous hash and hash didn't change.
The previous hash in block 3 before I changed the data is 000012fa9b916eb9078f8d98a7864e697ae83ed54f5146bd84452cdafd043c19 and hash
0000b9015ce2a08b61216ba5a0778545bf4ddd7ceb7bbd85dd8062b29a9140bf. This means block 2 hash is
000012fa9b916eb9078f8d98a7864e697ae83ed54f5146bd84452cdafd043c19 which is the same as block 3 previous hash.
This fact explains the intercalation between hash and previous hash
Clicking mine will bring about the validation of the block and make it easier for me to fine the actual hash.
Nonce: 89743
Previous. 000012fa9b916eb9078f8d98a7864e697ae83ed54f5146bd84452cdafd043c19
Hash. 000075fbeaca537fd301a1388958c1150c8cb5e681566013433955f42e7a4d6b

Although the third block have been validated, the previous block is still invalid even though the previous tag of block 2 is related to the previous hash of block 3
Block 4 (before)
Nonce. 35990
Prev. 0000b9015ce2a08b61216ba5a0778545bf4ddd7ceb7bbd85dd8062b29a9140bf
Hash. 0000ae8bbc96cf89c68be6e10a865cc47c6c48a9ebec3c6cad729646cefaef83

Block 5 (before)
Nonce. 56265
Prev. 0000ae8bbc96cf89c68be6e10a865cc47c6c48a9ebec3c6cad729646cefaef83
Hash. 0000e4b9052fd8aae92a8afda42e2ea0f17972ea67cead67352e74dd6f7d217c

Next i will click on mine for block 4 and block 5

Block 4 (after)
Nonce. 26660
Prev. 000075fbeaca537fd301a1388958c1150c8cb5e681566013433955f42e7a4d6b
Hash. 0000d01006f75e3669941836737b669b837bc7e6ffdc2feb07b8a0aa4963346e

Block 5 (after)
Nonce. 62463
Prev. 0000d01006f75e3669941836737b669b837bc7e6ffdc2feb07b8a0aa4963346e
Hash. 0000b8530466210a4454560cfc90246fc0191ef7075b8707cf36396ca5b9ce53
From screenshots above, it have been shown that previous hash and hash of next block are connected. So, changing any block will bring about the invalidation of the next block

Conclusion

Blockchain is a sophisticated and secured technology that stores information in blocks that are interrelated and linked to a server.
Due to the decentralized nature of of blockchain, it is secure and crystalline.

I really appreciate you prof. For opening my eyes to the effectiveness of blockchain technology.

Reference;

• Screenshots I took from https://andersbrownworth.com/blockchain/blockchain was edited on my smartphone.