ICT systems must be continuously updated. This is done to add new functionalities, fix bugs or fix security problems. A blockchain also needs to be updated every now and then. A soft fork can be used for this. In this way, the blockchain can switch to a new version without any problems. We are happy to explain what a soft fork is and how it works!
What is a normal fork?
When you think of a fork, you quickly think of a fork that you use to eat. That’s not what we mean in this case. Although the name comes from a real fork. We speak of a fork in the blockchain world when a blockchain gets a second version that simultaneously resembles the original blockchain. The separation created here can visually look like a fork. Hence the name.
Blockchains are open source. This means that anyone can view and modify the code. In this way, the blockchain can continue to develop. That is exactly the purpose of open source software. Everyone can contribute to the software, resulting in different versions. One version may be better than the other for your situation.
For example, a group of developers can decide to start a new, different version of a blockchain that runs simultaneously with the original blockchain. In most cases, a blockchain that arises from a fork does not survive, because there is too little support for such a blockchain. Enough nodes must transfer to the new blockchain in order to reach consensus in the blockchain network.
There are a total of two versions of a fork. These are the hard fork and the soft fork. Chances are you read more about a hard fork because you see it around you more often. A soft fork is generally a lot less visible, so less is known about it.
What is a soft fork?
In the introduction we talked about updating ICT systems. Blockchain also needs to be updated every now and then. The moment a group of developers decides to perform an update, they can start a soft fork. The blockchain is then copied and runs alongside the original blockchain. An update can then be performed here and tested for the workability of the update.
Then the original blockchain will be transferred to the new blockchain. Nodes are always communicating continuously to reach consensus. When a node sees that other nodes are using the protocol of the new blockchain, they will adapt themselves and update the protocol they are using. In this way, a blockchain switches from the old version to the new version.
But it can also go wrong. It has also happened that not all nodes switch to the new version. In that case, they will continue to work with each other according to the old version. A hard fork is then created.
The difference between a soft fork and a hard fork
A hard fork is also a separation from the original blockchain. However, the biggest difference with a soft fork is that the blockchains no longer come together. The old version will continue on its own without switching. In that case, it may be the case that the hard fork will continue to exist, or that it will eventually ‘extinct’, after which most nodes still switch to the new version of the blockchain.
But it can also be the case that the original version remains, or that two different versions of a blockchain are deliberately created. For example, developers of blockchain can disagree with each other and decide to make their own version and continue with it.
This is how Bitcoin Cash and Ethereum Classic were born. Due to disagreements about the future of the original blockchain, developers decided to create their own version and move forward with it. Nodes could then choose in which blockchain they wanted to continue working.
Is a soft fork better than a hard fork?
It is impossible to say which variant is better, because it is purely due to the reason for the fork. The moment an update is performed, and a dispute arises within the blockchain about the future, a soft fork can arise. The argument that is being made here is not good, while perhaps a lot is possible with these two different variants.
Can a hard fork always emerge from a soft fork?
Despite the fact that blockchain is open source, it is not always possible for a hard fork to arise from a soft fork. For example, there are plenty of private blockchains, which are controlled by a company, government or institution. They therefore determine the future of the blockchain, and therefore the chance is nil that a hard fork will arise from a soft fork in private blockchains.
Who decides whether there will be a soft fork?
Blockchain is open source, so no one owns the blockchain. Who decides whether a soft fork is made? The answer to this is fairly obvious, given that blockchain is open source software. Anyone can make a soft fork. However, the support must be large enough. If there are not enough nodes that want to participate, the execution of the soft fork will not be initiated.
The future of the blockchain is often voted on within the blockchain network. Participants of the network can then vote on the future plans by means of tokens, after which the plan with the most votes is carried out. This also makes it immediately clear whether there is enough support for the future plans of the blockchain.
However, the state of affairs differs per blockchain, because every blockchain has its own consensus algorithm , and represents a different vision. There is no general plan for soft forks that is the same for every blockchain.
Thanh Lanh Tran(1989) is Chief Editor from BitcoinUSD.com