Segregated Witness Enters New Testing Phase, But Some Can’t Wait for Hard Fork

As the Bitcoin community comes under increasing attack over scaling issues, the volunteer community responsible for developing Bitcoin’s open-source software code has announced that Segregated Witness (SegWit) testing has entered a new phase.

Seven months ago, Pieter Wuille, co-founder of Bitcoin startup Blockstream and important contributors to the Bitcoin Core open source development community, jointly proposed the Segregated Witness solution at the Hong Kong Bitcoin Scaling Conference to expand Bitcoin.

Since then, Segregated Witness (SegWit) has been extensively tested by the Bitcoin Core community and various Bitcoin-space companies, and recently Bitcoin Core contributors met in person in Zurich to conduct a hands-on review of the code.

Review: SegWit was proposed to effectively increase the capacity of Bitcoin transaction blocks by changing the way block space is used, rather than directly changing the size of blockchain data blocks. In addition, this upgrade addresses issues such as transaction ductility, or the ability to change a transaction ID before it is confirmed by the network.

By merging SegWit’s original code into the main branch of the bitcoin codebase, the new phase of testing will be made possible, developers say, and will provide more opportunities to stress-test the upgrade and identify many lingering bugs. The new phase can be tested along with SegWit and other functions of the bitcoin code.

Note: It will take some time for SegWit to be activated on the Bitcoin network.

First, the merged SegWit code does not include the components to activate these codes. According to the Core team, these activation codes will be written and added after more testing.

Wuille said:

“In the short term, we will just be patching and testing more real-world use cases on the testnet. After that, we will define activation parameters and release the SegWit activation code, and hopefully, it will be adopted by miners and the community.”

Pieter Wuille

On the other hand, the process of moving SegWit from scratch to real-world testing has not been without controversy.

Those who advocate for a direct increase in the block size believe that the SegWit expansion method is too complicated, and some even accuse the Core team of ignoring the interests of Bitcoin users - a claim that Bitcoin Core contributors have refuted. There are also some alternatives to Bitcoin Core, such as Bitcoin Classic.

Recent comments from members of the Chinese mining community and rumors that some miners may take it upon themselves to hard fork the network further illustrate how tense the current battle to scale is.

A matter of timing

One of the biggest concerns among some Bitcoin community members and stakeholders is when SegWit will be activated, even though it has already been merged into the Bitcoin testnet.

In conjunction with future testing, developers will embed SegWit into Bitcoin Core 0.12, which was released in February this year. In layman's terms, it means applying the new code to the old version.

Bitcoin Core maintainer Wladimir van der Laan suggested that this process could take place as early as next month, but this will depend on how the next phase of testing goes.

According to Wuille,

" It all depends on the timing, maybe it will be activated in Core 0.03.0 or 0.13.1 ."

In this case, developers involved in the project want to find all code defects (bugs). Given that the market value of Bitcoin exceeds $10 billion, any internal risks can lead to major changes in the functioning of the Bitcoin system.

Wuille said those risks are real, but Core contributors and others testing SegWit are aware of them.

“SegWit will undoubtedly significantly change Bitcoin consensus rules and implementation, so there are inherent risks. However, precisely because of the significant impact of this change, it will receive the most attention and the most rigorous scrutiny and testing. I believe that even if there are bugs left, they will be very small and will be discovered during the testing phase.”

Towards future development

In some ways, SegWit is just a stepping stone to other proposed improvements to the bitcoin code.

Van der Laan called last week’s integration “a huge step forward,” saying the introduction of SegWit creates opportunities for developers to add more functionality to bitcoin.

The release of SegWit coincides with other bitcoin developments, including a proposal from contributor Matt Corallo to reduce the time it takes for blocks to propagate through the network.

Wuille said:

“This is necessary because witness accounts cause block size increases, which makes the block propagation delay problem more urgent.”

Although the proposal may face criticism from Core opponents, the incorporation of SegWit shows that the development team of the Bitcoin Core team is making progress, especially now that some people believe that the Core team is conservative and unwilling to make changes to the Bitcoin protocol.