Core Developer Eric Lom on Misunderstandings in the Bitcoin Block Size Controversy

埃里克·洛姆, Bitcoin Core contributor and CEO of Ciphrex, recently spoke with Epicenter Bitcoin, a Bitcoin-focused podcast, about some of the myths and misunderstandings surrounding the block size debate.

The current development debate is focused on the actual block size in the Bitcoin protocol, which Eric Lomme says is missing the point of the debate. In his view, the Bitcoin Core development community wants to avoid a hard fork in the short term.

Hard Forks Are the Problem

In explaining the full block size debate, Lom suggested that the non-technical Bitcoin community may not fully understand what has been happening in the development community since May 2015. Lom described the debate that took place among developers during this time:

“I think a lot of the non-technical community and the public didn’t really want to see what the developers had done so far. We had discussed these ideas back in May when they were first proposed to the mailing list and people actually wanted to understand all the things that could have gone wrong. It was clear that the hard fork had serious stability issues and could lead to potential attacks that would be dangerous for the network.

Although simple soft fork deployments have also been carried out, hard forks are still being worked on. At the recent San Diego Blockchain Summit, Lom explained in detail BIP 9, which allows some new features to be applied to Bitcoin through a synchronous soft fork.

Contentious hard forks should be avoided

When discussing the deeper issues surrounding hard forks, Lom made it clear that such changes are not impossible for Bitcoin’s consensus rules. On the contrary, he believes that contentious hard forks should be avoided. Lom said:

I'm very concerned about hard forks. That's not to say that it's impossible to do a hard fork safely, but I think the only way it can work is when there aren't a lot of extreme opinions, and people aren't arguing about different opinions. If the vast majority of the network agrees on something - meaning it's basically non-controversial - that's great.

Bitcoin Classic is the Bitcoin protocol that increases the block size limit to 2MB. This block size change will require a hard fork, which will be activated 28 days after miners who support the block size increase find 750 of the latest 1,000 blocks.

Many Bitcoin Core contributors believe that the hard fork is controversial and hope to have 90-95% social consensus before forking. Although the Bitcoin network has never had a deliberate hard fork attempt (note: a change implemented in 2010 and activated in 2012 was similar to a hard fork), previous soft forks have been approved by 95% of miners.

We want bigger blocks

Lom said everyone wants to increase the size of the Bitcoin network by increasing the block size. He explained:

In terms of block size itself, I think larger blocks are fine. I don't think there's a lot of core developers saying, 'No, we're never going to have larger blocks.' I think in most cases, it's attractive to have larger blocks. We should find ways to do larger blocks; we want larger blocks. But increasing block size by changing a parameter in the code leads to very, very serious problems.

In other words, Bitcoin Core contributors hope to find a block size increase solution that will not cause a contentious hard fork.

Segregated Witness is the best of both worlds

So far, the concept of increasing block capacity without a hard fork has remained theoretical. Bitcoin Core developer Pieter Wuille presented Segregated Witness (SegWit) at the Scaling Bitcoin Summit in Hong Kong to generally positive reviews. Lom described how the proposal provides the best path for developers:

If we want to scale safely, we have to improve some things and do a lot of risk mitigation, and that's what we're working on. With SegWit, we get the best of both worlds. I mean, yes, it's no longer a single code parameter change - it does require a little bit of change - but it's not a big change. And it's safer in other ways. It doesn't have the stability issues that you would have if you changed a parameter.

Some critics of the Segregated Witness soft fork have argued that the changes to Bitcoin wallets required by the plan are too onerous, but Lomm said the wallet developers he worked with were able to implement the required changes in a matter of days. The Bitcoin Core website also lists a list of wallet providers that plan to support Segregated Witness.

Soft forks are almost easy

In Lom’s view (and according to the Bitcoin Core development roadmap), a SegWit soft fork is almost a no-brainer. Ciphrex’s CEO explained:

“Block capacity is never the real issue; it’s not the real issue that people are arguing about. The real issue is about hard forks — do we need hard forks? Since we have a soft fork solution, it’s easy.”

Lom went on to say that the basic consensus of the Bitcoin Core development community is that the current network cannot handle blocks larger than 2M. This means that a hard fork larger than 2M is likely to fail to gain consensus among Bitcoin Core contributors.

Original text: https://bitcoinmagazine.com/articles/bitcoin-core-developer-eric- lombrozo-on-misunderstandings-in-block-size-debate-1455817458
By Kyle Torpey
Translator: Next (8btc.com username)
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