Minicrypto Academy part3||"Understanding of blockchain", by @abduljawad002

Hello @liasteem It is my esteem pleasure to part take in your mini crypto program and am hopeful to gain more insight into the world crypto. This is my knowledge about blockchain after reading and understanding the lecture notes provided by you.

Question 1

What do you know about blockchain??
As we hear about blockchain most people doesn't even know what it really means neither did I until now . After reading the lecture notes you provide, it has given me much more insight into what blockchain really means. In lay man terms, we could say that blockchain is a long array of blocks connected by chains as the name suggests, where the blocks denotes the data being stored from users and the chains denotes the nodes of communication between the blocks of data .

Blockchain is a decentralized system which stores data through cryptography which ensures a high level of security and distributes all the data to nodes online. Blockchain is mostly seen to save time and and energy as its technology is so advanced that anyone can access the data and the transactions of other user without the need of permission from anybody and all at our place of comfort from either laptop or a smartphone.

Blockchain protocol is formed on the basis of three main features stated as follows

Block

This makes it possible for the storing of all the data and information and connected by the nodes. The data in this feature store data incase for security reasons and also determines the validity of data through the hashing system. Each block has a unique hash which makes it high impossible for a user to gain access to control the system.

Node

Nodes are the important part of the whole blockchain system. They make communication of data with other nodes and the whole blockchain operation possible and also contains a copy of the transaction history of blockchain

The miner

Is a process used to create new blocks into the blockchain. Since each block has a new hash so to be able to change hash in the block, the miner will have to re mine the whole new block

Question 2

Describe one type of blockchain
There are mainly four types of blockchain which i will like to talk about but mainly focus on one of them.
1 - Private Blockchain: Private blockchain is a centralized system mostly used in organizations. It is mainly controlled by the organization and unlike public blockchain you need permission to be able to access data or information in the network.

2 - Consortium Blockchain: Consortium blockchain is made up of some features of both private and public blockchain. Therefore this system is not controlled by a central authority and neither is it public, but only accessible to user in that blockchain network.

3 - Hybrid Blockchain: Hybrid blockchain is almost similar to the consortium blockchain as in it is also made up of both part of the public and private blockchain. But in this type of blockchain the user has the power to decide which type of blockchain system they want to use that is either public or private.

4 - Public blockchain

I will like to talk about the public block chain into details because i thinks its the best. This is the first type of blockchain technology to be ever created. This technology helped popularize the distributed ledger technology and removed the problems that came with centralization and transparency.

With public blockchain anyone with an Internet connectivity can sign up on the blockchain platform to become an authorized node and can also access past and current records on the network as well as perform mining activities.

This type of blockchain is meant for ideal or potential organizations that are built on transparency and trust such as non government organizations. The public blockchain can also be used for creating a fixed record with an auditable chain of custody.

The public blockchain is independent of organizations, so if the organization that started it collapses, the public blockchain will still function as long as there's still connectivity. The network transparency are mostly secure with the public blockchain.

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Question 3

Explain the advantages and disadvantages of the type of blockchain you choose
Lets talk about some of the advantages and disadvantages of the public blockchain.

Advantages

Transparency

Blockchain uses a distributed ledger which stores transactions and data into multiple locations. And all personnel with authorization can access information at the same time providing full transparency. It helps very entire history of transaction and virtually reduced the risk of fraudulent activity.

Efficiency and speed

The processes with blockchain has been made more easier which causes transactions to be completed faster and efficiently. Blockchain stores the documentation of transaction details removing the need for the traditional paper system.

Security

Data is important and sensitive and blockchain can easily change how important data and information is viewed by creating a record that is end-to-end and can be changed. Privacy issues in blockchain is addressed by annonymizing personal data and uses authorization to prevent access.

No third parties

Blockchain eliminates the need for a third party by providing an impartially logical system to Make transactions easier and trust worthy. And with no involvement of third parties like the government also makes it impossible to manipulate the value of the currency.

Disadvantages

1 - Network issues: Since the size of the system is large there are many nodes connected to the blocks, thereby making the rate at which transaction are validated very slow as compared to the private blockchain.

2 - Minor collision: In the public blockchain system there is a chance of minor collision because there isn’t any central authority to check the validators to see if they meet certain standards before they can validate. In this system no one knows they validators so there is a chance for a minor collision.

3 - Consumes a lot of energy: This type of blockchain consumes a lot of energy in terms of mining, super computers are required to solve complex problems so in doing so they consume lots of energy.

Question 4.

Visit Blockchain Demo and what did you learn from that page?

When i opened the site i was provided with and empty page with a hash and according to the knowledge i gathered from this course the hash provided is invalid because it didn't start with zeros.
e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855

I then typed in a text (abduljawad) in the box space provide which provided a different hash as seen.
5b190eeab33d2bcd625081c8b2e4627a35f0607f00417f080b35d8b1c4ff53cd

I also learned that the smallest changes in data can create a new hash so i change the text (Abduljawad)and as seen it provided a different hash.
31c4e36040316b44e5cd3f0bd1fa8f3c2fb3a152fc5d47637683e983a902c22d

Now lets move to explore for ourselves

When you open the site you will see this page they are five boxes but i will just limit it to two

You see for every block number and Nonce number you have a different previous hash and
new hash. So for block number 1 and Nonce 11316 we have prev: 0000000000000000000000000000000000000000000000000000000000000000
Hash: 000015783b764259d382017d91a36d206d0600e2cbb3567748f46a33fe9297cf
and for block 2 and Nonce 35230 we have a prev :
Hash:
Adding data into the block

After adding data in the the space you see the hashes changes. So for block 1 and Nonce 11316 we have a new prev: 0000000000000000000000000000000000000000000000000000000000000000
Hash: 9ea0f382f71f388473c1377fed99c17eaf700ea1000e0f0ed569cce6946b056e
and for block 2 and Nonce 35230 have a prev: 000012fa9b916eb9078f8d98a7864e697ae83ed54f5146bd84452cdafd043c199ea0f382f71f388473c1377fed99c17eaf700ea1000e0f0ed569cce6946b056e
Hash: 2ccfe858fe81efdabd49671c7c13d5e173dbe3b078a29190462a7df24cdfa5f9

Question 5

Explain the advantages and disadvantages of using blockchain technology

Advantages of blockchain technology

1 - Fast Transactions: The main feature of a private blockchain is its small size, since it has limited number of blocks the validation of every block will be faster than the public blockchain which has plenty blocks.

2 - Decentralized systems The public blockchain system is purely decentralized which is not controlled by any central authority but is run by the people. Because of that the users are free to do what they want without worrying about any central authority.

3 - Transperency: This system is such that users from all over will be able to see the transaction details at anytime with this no one can lie about anything this helps improve transparency among the users.

Disadvantages of blockchain technology

1 - Restrictions: Since it is not decentralized and controlled by central authority certain nodes restrict the user from accessing certain aspects of the network.

2 - Manipulation: Since the platform is controlled by a central authority it can be easily manipulated to suite their personal desires

3 - Security The security of the private blockchain is less secured and is prone to hackers I say this because in the private blockchain the codes of the organization are hidden from the users to see and to confirm its durability and also since the entire system is managed by central authority it can easily be manipulated.

Conclusion
I must commend @liasteem for the opportunity to learn this much abt blockchain. i really enjoyed the lecture i learnt about how doubled spending is countered by introducing a ledger feature and how the smallest change in data can cause a change in the hash.
Thank you