Following the hard fork in the Ethereum blockchain earlier this year, developers involved in the Bitcoin Core project are coming up with a plan to deal with the possibility of a hard fork in Bitcoin. But with the Bitcoin network much larger and more disparate than Ethereum, could such an event happen with Bitcoin anyway?
A Hard Fork
A hard fork is when a blockchain splits in to two based upon a fundamental change in rules governing the system. In the case of Ethereum, the hard fork that was initiated was the result of a hack in TheDAO, a smart contract that had some bad code with which to exploit. This exploit allowed the hacker to siphon off tens of millions of dollars worth of digital currency. A hard fork was used to roll back those illicit transactions and return the stolen funds to their rightful owners. (For more, see: Ethereum Reaches Consensus to Hard Fork, Fixing DAO Hack)
A hard fork in Bitcoin seems to be much less likely. First, the size of the Bitcoin network is much larger in terms of mining power, even though there are approximatetely the same number of nodes in the network. This is because many Bitcoin miners pool their resources collectively – but are free to move from pool to pool. Another reason is that Bitcoin does not employ the same level of smart contract compatibility. Ethereum was developed specifically to handle Turing-complete code, while Bitcoin’s handling of scripting is more rudimentary. As such, the chances that an exploit could be found in a Bitcoin script are lower. Lastly, Bitcoin is an older, more tested system that has dealt already with numerous upgrades and patches (soft forks).
Preparing for the Unlikely
Still, the debate over how to scale up the Bitcoin system to account for more (and more frequent) transactions is largely unresolved. The so-called block size debate could potentially lead to a hard fork if the problems compound without a consensus solution. As such, the Bitcoin Core development team is taking proactive steps that amount to a new responsibility the network’s mostly volunteer coding group has taken on as the protocol has grown.
According to CoinDesk, “In this light, there has been a renewed emphasis within Bitcoin Core to explore how it could implement a hard fork, a type of protocol change that has proved a lightning rod for controversy during bitcoin’s ongoing scaling debate and resulted in schisms in other blockchain networks…No one has pulled off a hard fork on a working system swimmingly with a clean system coming out on the other side. A number of people working on Bitcoin Core think we should have an idea of how [a hard fork] should look.” (See also: The Future of Cryptocurrency)
The Bottom Line
While a hard fork on the Bitcoin blockchain is unlikely, given recent events on Ethereum, it seems prudent to begin planning for its eventuality just in case. These proactive steps are now being undertaken by the Bitcoin Core development team with hopes that if a hard fork does ever happen, it will occur smoothly and as little negative side effects as possible.