比特币面临分裂风险

上周五，几家大型加密货币交易平台联合发布声明，宣布了他们对于比特币可能出现分裂的处理决定。这种分裂被称作“硬分叉”（hard fork）。多年来，比特币领导者在这种货币的网络技术限制和对未来的愿景上争执不休，愈演愈烈，分裂的可能性也日益增大。

上周五发布声明的包括大型门户网站BitStamp和Kraken，他们表示，如果出现硬分叉，他们会允许用户交易这两种传统比特币，以及任何可能出现的新版比特币。最有可能拆分的方案叫做Bitcoin Unlimited。它近期获得了全球最大的比特币服务器组，也就是“挖矿组织”的支持。

比特币之所以被推向分裂，主要是各方对于所谓的“区块大小”（block size）争执不下。按照现有的代码，比特币每批交易的数据容量有严格限制，随着比特币热度日增，这种限制拖慢了交易，以往只需数秒就能清算，现在得花上好几个小时。各方都认为有必要对此做出改变。

然而，对于改变的目标和方式，大家却没有达成共识。一位比特币的企业家很好地总结了两派的分歧：Bitcoin Unlimited一派希望升级比特币，支持更多的小规模交易，而Bitcoin Core一派则认为不应如此大刀阔斧，他们希望交易少一点，让系统更加稳定。

比特币的管理十分松散，甚至有些无政府主义，这让改革难以推行。比特币主机（“矿工”）本质上可以通过选择运行的软件来对系统的改变进行“投票”。然而如果许多矿工运行了互不兼容的代码，就会产生不同的交易记录，实际上也就意味着创造了完全不同的货币。

Silicon Angle指出，目前有近40%的比特币矿工支持Bitcoin Unlimited。这个比例还不足以迫使比特币进行大规模的系统性改变，采纳新协议，不过也足够形成一个举足轻重的派别了。

交易平台这次的声明可能有助于减缓潜在的硬分叉引发的混乱。去年，加密货币已经有了类似先例，影响力堪比比特币的Ethereum为了阻止黑客获得数百万美元的货币，按照计划进行了分裂，却意外地形成了两个相互竞争的系统，据报道，它们会彼此干扰对方的运作。

如果比特币中最具影响力的成员决定分道扬镳，那么提前做好规划看起来是最合适的选择。（财富中文网）

作者：David Z. Morris

译者：严匡正

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.

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.