What Happened to Bitcoin: A Recap of the Blockchain's Big Split

It wasn't the first attempt to fork the bitcoin blockchain, but it was certainly the most memorable.

As reported earlier today, Bitcoin Cash, a new cryptocurrency, was created when a group of miners "forked" from the main bitcoin blockchain – in short, they switched to a new, incompatible software that changed the rules by which the network would function.

Over the course of the day, miners backing the project succeeded in officially branching off, ultimately adding blocks to the separate blockchain, and in the process, building what they believe could come to be a growing economy centered around its development.

In doing so, they also marked the end of a controversial effort that began as just one of many ways to chart a new technical roadmap in the face of a wide range of alternatives.

As developer and Paxos principal architect Jimmy Song predicted earlier this week, the day's defining moment came at around 8:20 a.m. ET – the time miners running the new software had agreed to begin diverging from the main chain.

That pivotal period started at approximately 12:37 p.m. UTC (or for those keeping time in bitcoin terms, block number 478,558), as it was then that Bitcoin Cash miners began to seek what would become the new network's first block.

Here, they were working under specific constraints – the block had to be larger than the standard 1 MB size limit still imposed on the main bitcoin blockchain.

Yet, as detailed on CoinDesk's live blog (which you can catch up on here), the creation of first block perhaps took longer than supporters had hoped.

Given the relatively small amount of miners running the new software, and the fact that the software carried over with it the same difficulty that regulates how easy it is to find blocks based on the number of miners, Bitcoin Cash struggled to keep up with the main bitcoin network, which quickly grew in size.

Indeed, as hours passed, some observers began questioning whether miners would continue the pursuit at all (given that they were missing out on bitcoin's mining rewards by doing so).

The idea emerged that Bitcoin Cash could go as long as a day without a new block, given the difficulty and the low hash rate, circulated among some observers.

BitGo engineer Jameson Lopp ultimately had the closest call: "It's likely going to take at least several hours," he tweeted.

Then, it happened.

At about 6:14 p.m. UTC, ViaBTC mined the first Bitcoin Cash block, which came in at a block size of 1.915 MB. That block contained 6,985 transactions, according to public data.

Since then, four Bitcoin Cash blocks have been created, though only the first of the initial five had a block larger than 1 MB. By comparison, the most recent block contained 520 transactions, using about 0.4 MB of space in the transaction block.

With the creation of those blocks, Bitcoin Cash entered a new phase in which it became an actual network – albeit one that was given to delays.

The block's passage also seemed to spur launches on digital currency exchanges, with trading now live on bourses like Kraken, TheRockTrading and OKCoin, among others.

As for what's to follow, it's really up to the market to decide.

With exchanges listing the coin and newly-found Bitcoin Cash owners taking control of their assets, one of the big questions will be what happens with the price of the digital asset.

One prospect that does seem likely: a sea-change in the tenor of the years-long scaling debate, the disagreements over which arguably led to the events of today.

When it comes to bigger blocks or a more nuanced approach – it seems it's now up to the market to decide.

Rewind button image via Shutterstock