A Hitchhiker’s Guide to Hard Forks

May 25th, 2018 at 7:13 pm UTC · 6 min read

Similarly, a blockchain fork happens as a result of changes made to its original code or protocol by developers. This can be due to a number of reasons:

  • Developers want to add new features and functionalities to the blockchain
  • They want to alter the existing rules of the blockchain to improve its ecosystem
  • They want to create a new cryptocurrency

A fork usually results in a blockchain split i.e. two versions of the blockchain are formed. Depending on how the change in rules is implemented, a fork can be a soft fork or a hard fork.

In this article, we’ll briefly discuss the differences between soft and hard forks, and then we’ll talk about the different kinds of hard forks:

  • planned hard forks that are a direct result of the developers and the community choosing to upgrade the existing protocols of a blockchain,
  • contentious hard forks that arise due to disagreements within the community on which protocols of a blockchain to keep or replace,
  • source-code hard forks that look to create entirely new blockchains with a new set of features.

At the end, we’ll talk about how an upcoming blockchain project is gearing up to hard-forking five major cryptocurrencies into a single, more sustainable, more secure blockchain. So, keep reading and let’s dive right in!

Soft Fork vs Hard Fork

A soft fork is a change to the blockchain protocol that narrows down the set of rules enforced on the blockchain. For example, developers may choose to limit the block size from, say, 1MB to 500kB.

This allows every node on the network that is working by the old rules (i.e. they haven’t updated their software or wallets to the version with the new rule set) to still take part in validating and verifying transactions (because 500kB is still within the upper limit of 1MB).

Therefore, a soft fork is said to be backwards-compatible and easier to implement.

But what if you were to update the blockchain protocol to increase the block limit, say from 1MB to 2MB? What would happen?

Nodes on the network that do not upgrade to the new rule set will reject the new blocks and be unable to validate them (as the size is well above the 1MB limit). In this case, to participate on the new chain with the new rules, a node will have to upgrade its software (or implement a new one).

Such an upgrade in the blockchain protocol that expands the rule set (to add new functionalities), and is not compatible with older versions is called a hard fork.

In a hard fork, all participants must upgrade to the new software to continue to validate transactions. This results in a permanent divergence of the blockchain, and as long as there is support on both its older and newer versions, the two chains will exist concurrently.

Now, there are three major types of hard forks — planned forks, contentious forks and source-code forks. Let’s discuss them one-by-one.

Planned Hard Forks

A hard fork is planned when a blockchain protocol is upgraded so that an old set of rules is abandoned in favor of new ones. It is usually a part of the blockchain project’s roadmap and is implemented to enhance its capabilities.

Development on the old chain is discontinued and the entire community moves forward on the new chain with a new set of rules and enhanced capabilities. A planned hard fork does not result in the formation of a new coin.

For example, Monero upgraded its network in January 2017 by conducting a planned hard fork on its blockchain to implement an adapted version of Confidential Transactions called Ring Confidentiality Transactions (RCT).

This upgrade vastly improved the blockchain’s security, privacy and anonymity. All of the network’s nodes promptly made the transition to the new chain and business carried on as usual.

Contentious Hard Forks

A contentious hard fork happens when a blockchain community is divided on whether or not to implement certain changes in the blockchain rules, and a portion of them goes ahead and creates a new chain by making the changes they want to the blockchain code.

Now, because the rest of the community continues to support the old chain, this results in the creation of two competing, actively developed chains with different sets of rules.

Usually, the old chain continues to hold its original name and network while the new chain is given a new name. Thus, a contentious hard fork results in the formation of a new coin.

For example, Bitcoin was hard-forked by a portion of its community that wanted to increase its block size from 1MB to 8MB. This resulted in the formation of a new coin called Bitcoin Cash. Bitcoin Cash allowed for more transactions to be processed and brought down user fees considerably.

Source-code Hard Forks

Many public blockchains are open-source i.e. everybody has access to their core code base. Changes made to the code base of a blockchain results in the formation of a new blockchain that can be entirely different from the one it’s derived from (based on the changes in its code).

This type of fork occurs not at the functional level of a blockchain but at the core developmental level. The new blockchain is launched afresh with a new genesis block and does not share transaction history with its ‘parent’ blockchain. A source-code fork results in the creation of an altcoin.

For example, Litecoin was a source-code fork of Bitcoin. Its code base was a fork of Bitcoin’s code base and was launched with an entirely new genesis block. It shares no history with Bitcoin transactions and is considered a separate alternative cryptocurrency.

Introducing the World’s First Multi Cryptocurrency Fork

The Bitcoin Origin Foundation is set to launch the world’s first penta-cryptocurrency hard-fork, merging five major cryptocurrencies into one multichain blockchain via simultaneous contentious forks.

The contentious forks will result in the formation of a new coin called Bitcoin Origin (ORI). The new multichain fork will be an advancement in technologies of the five biggest Proof of Work cryptocurrencies, namely Bitcoin, Bitcoin Cash, Ethereum, Litecoin and Dash.

It will, however, feature a variant of the Proof of Authority consensus protocol called Proof of Ambassador instead.

The Proof of Ambassador protocol will be a combination of two major consensus methods — Proof of Stake and Proof of Authority, and will enable a high transactional throughput of 15,000 transactions per second on the blockchain.

Improvements Over Existing Blockchains

  • Bitcoin Origin will support an incredible 15,000 transactions per second
  • It will be one of the most energy-efficient cryptocurrencies currently in existence
  • It will make use of ground-breaking, innovative blockchain protocols like multi-state engines (MSE), cross-chain, multi-layering and namespace sharding to let users of any technical skill implement their own native, serverless blockchains
  • That will in turn solve the problem of economic abstraction
  • The use of an Ethereum Token Bridge on the blockchain will allow for dApp fees to be paid in your own native tokens


Magdél Steyn

[email protected]