Crypto Academy / Season 3 / Week 4- Homework Post for Professor @awesononso - Topic: Blockchain Forks.

Block chain which is like an upgrade of the internet is a system recording information in way that it is impossible to hack or change a blockchain technology while some will say block chain technology are digital ledgers of transaction that is duplicated and shared across the systems in a blockchain.

In this weeks lecture from @awesononso he wrote about blockchain forks and how it can be used in resolving issues when there is an issue, below i answered all the question given.

Question number 1: WHAT IS A FORK? (IN YOUR OWN WORDS)

In the path to reveal what a fork is we need to know what is a blockchain, a block chain is an open source software, which means it is available to everyone and can be used and changes can be applied and that is when a fork as taken place.

This means when ever a fork as occurred on a blockchain then the blockchain has been changed or misaligned, if all the miners of that particular blockchain decides to abandon the old blockchain for a new one then with time the blockchain will rearrange or reposition and that crypto community will go on to enjoy the feature of the new blockchain.

If on the other hand there wasn't any decision to abandon the old blockchain and they continued with it while the other miners get a new blockchain path then it will create two versions of thesame blockchain.

Source

Fork is the change in the software protocol of any blockchain which causes a slip in the network, this split can lead to just a simple restriction of the blockchain or to the creation of two different blockchain, There are two types of fork and they are hardfork and softfork.

Question number 2: EXPLAIN IN DETAILS WHAT A HARD FORK IS WITH EXAMPLES (CAN BE OF ANY BLOCKCHAIN).

WHAT IS A HARDFORK
Hardfork is the type of fork which develops when the change in a blockchain is so radical, to the point that the newly created blockchain is incompatible with the old blockchain protocol, this splitting leads to the creation of twp new blockchain.

It can be intentionally that the blockchain protocol change, but it doesn't matter what caused the change, if some miners in the blockchain who don't approve of the created in the blockchain continue mining activities with the old blockchain protocol, it will lead to creation of two more blockchain.

It doesn't make sense and it worth nothing if those who continue mining with the new blockchain will have the same number of coijs they have in the original blockchain, before any change in the protocol has be carried out, this is because even though they are different blockchain they still share a common origin.

However, from the point of post fork, the old blockchain version will still be running with the old protocol while the changed protocol will have the new blockchain running on it.

Those users or community members who wants to continue with the new protocol will require to upgrade their software so as to be able to verify and validate transactions in the new blockchain because hardforks are not backward compatible.

EXAMPLE OF HARD FORK

Ethereum and Ethereum classic

According to source there was an event that occurred in 2016, in that year a very good hacker hacked ethereum and was able to steal $3.6 million of ETH, then a meeting was organized in the ethereum community to try and replace $3.6 million which was stolen.

In a bid to solve the issue, a consensus was reached and majority of the community chose to fork the blockchain and continue with a new blockchain which is ethereum, while some users disagree by saying the want to continue with the original blockchain but renamed and is known as ethereum classic

To prove this you can visit ethereum and ethereum classic block explorer, you will see that both blockchain have something similar and that is their Genesis Block 0 is the same with the same hash:

Ethereum classic block 0

Ethereum Block 0

Their blockchains also share the same records of transaction before the splite, Example Block 100r both Ethereum and Ethereum classic is the same, with hash.

Ethereum Classic Block 100,000

Ethereum Block 100,000

Ethereum and Ethereum classic stop sharing every consequent transaction records for instance, the hash for block 10,000,000 for Ethereum is 0xaa20f7bde5be60603f11a45fc4923aab7552be775403fc00c2e6b805e6297dbe

Ethereum Block 10,000,000

While the hash for block 10,000,000 for Ethereum classic is 0x83bd7d679c4045bc71cba8ed60d2c9263a5e2ef101b1f3b36dd77c5007b53088

Ethereum classic Block 10,000,000

QUESTION NUMBER 3: EXPLAIN IN DETAILS WHAT A SOFT FORK IS WITH EXAMPLES (CAN BE OF ANY BLOCKCHAIN)

Soft fork as the soft implies simple modification that are carried out on the blockchain( like adding new features). Although there will be a change in the blockchain's protocol, it nodes are still compatible with the original version.

Majority of the miners has to agree to upgrade the protocol in other for it to work, Those miners who did't upgrade will still be able to validate and verify transaction in the blockchain, Softfork is backward and compatible unlike hardfork that is the reason.

The miners must update their system so that their nodes can be able validate transaction but that is after softfork has taken place, because although the nodes from the new blockchain can recognise the old blockchain, but the old block chain will not be able to recognize the new blockchain, it is similar to when you want to update a software in your phone or pc.

Example, A block size which used to be 1200kB became 800kB in the updated version, mining will be rejected for the users who have not yet upgraded but they will still be able to see the income of new transaction as valid.

Softfork structure

The reason is because the new protocol rule is that the minimum size of any block must be 800kb, but since the old version will be accepting only 1200kb of block size it won't work that is why every user who want to keep mining in the platform will have to upgrade to the new protocol so that the can mine.

THE EXAMPLE OF SOFT FORK

Segregated Witness

Segwit is the most popular softfork in the world of blockchain, it is a softfork of bitcoin blockchain, those who created segwit realize that there is no need in always increasing the size of bitcoin block, because as you increase the size you need more hardware to run a node, they decided that is best because the size of bitcoin block can be pegged at one megabyte just as satoshi the developer wanted in 2010.

They developers created segwit in a bid that in other to modify a block so that it's maximum block size is 1MB, while still keeping the goals of the mysterious satoshi nakamoto, The segwit is literally a change in bitcoins block chain protocol which include removing witness data from the input list.

Witness data is needed to verify the validation of a transaction, however when it comes to determining transaction effects it is not needed, therefore the removal doesn't determine the status of the transaction, the removal of witness data considerably reduce the size of bitcoin block.

Even when this modification is a good one there was still some participants who disagree with this segwit idea, they believe that reducing the block size will considerably decrease the number of transaction that is carried out in the blockchain per second and for a crypto intending to remain the dominating cryptocurrency in the crypto community, this ain't a good idea.

As we know that soft fork doesn't require the approval of every participant rather just that of the majority but this majority that support of segwit still went ahead to modify the blockchain protocol, those who are not in support of the segwit and have refused to upgrade can still verify the transactions in the blockchain, but their functionally in considerably reduced for example they can't mine till they upgrade their node.

QUESTION NUMBER 4: WHAT ARE THE DIFFERENCES BETWEEN HARD FORKS AND SOFT FORKS?

Hard fork and soft fork can split blockchain but they are different, I will be explaining the difference below.

SoftFork	HardFork
Compatible backward	Incompatibly backward
Can't create new crypto	can creat new crypto
No repetition of block in the softfork	there is repetition of block in the hardfork
The approval of majority is required	The approval of all is required
Reconfigure an already existing blockchain	creates a new blockchain

QUESTION NUMBER 5: EXPLAIN THE FOLLOWING BITCOIN FORKS AND EXPLORE THE BLOCKCHAIN WHERE NECESSARY. INDICATE IF THEY ARE HARD FORKS OR SOFT FORKS; BITCOIN CASH AND SEGREGATED WITNESSES

As you can see i wrote about segwit above and i will like to continue writing about it before writing about bitcoin cash.

Segregated Witnesses

The proposal of Segwit led to the forking of bitcoin blockchain, they knew that there was no wisdom in constantly increasing the size of bitcon block, because each increase will result to the need for more hardwares to run a node. They believed that it was best that the block size be pegged at 1MB per block.

Do you know that the idea of segwit is not to create a new blockchain or a new crypto, but rather to make slight modification in bitcoin blockchain protocol in order to achieve this idea the best option was softfork.

As we know softfork doesn't require the approval of all just majority but the majority who approved it still went ahead to modify the blockchain protocol.

Those who don't like segwit and have refuse to upgrade can still verify transaction in the blockchain, because hardfork is backward compatible, they only limitation they have is still their functionality is considerably reduced, for instance, a block can't be mined in the block chain until they decide to upgrade.