Bitcoin Prepares For an Ugly Breakup

On Friday, a group of major cryptocurrency exchanges announced their planned response to the split of bitcoin into two separate pools of currency and processing power. That event, known as a “hard fork,” is viewed as increasingly likely among bitcoin leaders, as a years-long debate about the network’s technical limitations and broader vision comes to a head.

The marketplaces, including marquee portals BitStamp and Kraken, said on Friday that if a hard fork occurs, they will let users trade both conventional bitcoin, and any alternate version that emerges. The most likely bitcoin spinoff is known as Bitcoin Unlimited, which the world’s largest bitcoin server group, or “mining pool,” recently announced it would back.

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Bitcoin has been pushed to the verge of this split by a years-long debate about what’s known as block size. Under bitcoin’s existing code, there’s a tight limit on the amount of data that can be included in a batch of transactions, and as the network has grown in popularity, that limit has slowed the processing of payments. Moves that once took seconds to clear can now take hours, and all players seem to agree that some sort of change is necessary.

But there are competing visions about any fix’s goals and methods. One bitcoin entrepreneur has summarized the divide as between a Bitcoin Unlimited contingent updating bitcoin to support many small transactions, and a Bitcoin Core cadre who believe in smaller changes, fewer transactions, and more stability.

The decentralized, even anarchistic nature of bitcoin administration makes the process of change unwieldy. Bitcoin hosts (“miners”) essentially ‘vote’ on any system changes by choosing what software to run. But if large groups choose to run mutually incompatible code, they generate separate transaction records, and in essence, entirely separate pools of currency.

Currently, according to Silicon Angle, nearly 40% of bitcoin miners support Bitcoin Unlimited—not enough to force a system-wide changeover to the new protocol, but enough to establish a splinter group.

The exchanges’ announcement may help smooth the potential chaos of a hard fork. The crypto world got a preview last year when Ethereum, a major bitcoin alternative, underwent a planned fork to reverse the results of a multimillion dollar hack. That unexpectedly led to two competing systems, which reportedly interfered with one another’s operations.

If bitcoin’s big players want to go their separate ways, then, some advance planning seems very healthy.