Bitcoin expansion debate: will the realization of “big blocks” still depend on Bcoin?

As the two-year bitcoin scaling debate rages, few software have advanced enough to replace the bitcoin network’s most popular and longest-running software, Bitcoin Core.

The relatively famous ones are Bitcoin XT and Bitcoin Classic. Both software give priority to larger blocks to support more transactions.

(The debate over Bitcoin expansion has lasted for two years Source: Golden Finance)

However, as a side effect of their ambitions, network users will need to switch Bitcoin implementations to implement these changes, something not everyone is willing to do.

This development reveals a strange aspect of the scaling debate — one in which alternative solutions need to come up with a technical modification — and assemble their own team of developers — as the price of their alternative view.

One of the more popular alternative solutions is Bitcoin Unlimited, which allows miners and users to line up to support the block size they want, but their code is full of bugs - or, at least, it is not mature yet. For example, in March of this year, attackers exploited such a bug twice, each time causing the majority of the network's network nodes to shut down.

In this context, an implementation called Bcoin (created by bitcoin startup Purse) has entered the scaling debate and could become a climax in the scaling drama.

The software project introduced its own previous expansion idea, “extension blocks” or e-blocks, which the company described as a way to bypass today’s block size stagnation. The solution was touted after it was announced this week.

This idea is controversial and has sparked various complex technical discussions since its announcement. Some developers believe that adding "extension blocks" is unsafe.

Still, there is strong support for the extension block, largely due to the experience of the development team. Notably, Bitcoin Unlimited supporters have already expressed praise for the project.

For example, ViaBTC mining pool CEO Haibo Yang told CoinDesk that he supports Purse’s concept and the Bcoin team.

Yang Haibo said:

“I think extension blocks are going to be a solution moving forward.”

The “promising” option

Overall, there is growing consensus that Bcoin, an alternative software implementation of Node.js (a JavaScript runtime) launched last September, has a stronger technical team than Bitcoin Unimited and other so-called “big block” teams.

For example, Purse CTO and Bcoin developer Christopher Jeffrey was praised for building the software and implementing a work-in-progress lightning network called Plasma (Lightning Ions) that can be built on top of the software.

Meanwhile, Lightning Network co-author Joseph Poon also helped write the parameters for Bcoin’s implementation of the recently introduced flagship technology.

One of the reasons supporters believe the team is trustworthy is that the BTC.com mining pool mined a block in March by running the Bcoin software — purportedly the first block to be mined by a client not based on the bitcoin source code.
Purse has released a technical draft and reference implementation code for implementing extension blocks on top of Bcoin.

This is not to say that Bcoin is trying to replace Bitcoin Core like other implementations. When the company first introduced Bcoin, it described it as a Bitcoin alternative with cleaner code that could coexist with other software versions.

Differences remain

Although Yang Haibo is confident about the extension block, not all BU supporters are.

For example, Olivier Janssens, a former board member of the Bitcoin Foundation, criticized the solution for being too complicated. He told Coindesk that Bcoin’s idea was “too complicated.”

“People need to get over their fear of hard forks,” he said.

Still, many are positive about the solution, even if they may be more focused on other options for scaling.

“I like extension blocks, but I think there’s little risk in actually increasing the block size,” said Roger Ver, a bitcoin investor who runs Bitcoin.com and is one of the most outspoken advocates of alternatives to Bitcoin Core.

Bitcoin Unlimited developer David Jerry Chan compared the technology to other available solutions.

“I think this proposal makes sense and is better than SegWit.

Chan also said that Bitcoin Unlimited developers are still discussing the proposal and that the team has not yet given an “official opinion.”

However, there are potential nails. For example, one of the criticisms of Bcoin is that no matter how good its technical team is, Becoin still needs time to be audited. (For example, Segregated Witness was audited and tested for about a year before it was released.)

On the other hand, Purse CEO Andrew Lee believes that the Bcoin code is already available, so the review time may be shorter.

In fact, according to the technical announcement, the next step is to deploy Bcoin on the Bitcoin test network for further review and specification improvement.

Yang Haibo also thinks so, and he concluded:

"We have been waiting for more than a year, so another three months is fine."