Bitcoin users have kept a close eye on the BIP91 lock-in period. This lock-in has now been secured with relative ease. However, there is no reason to get your hopes up just yet, as this lock-in period means nothing until things change on the network itself. Signaling intent for a solution and effectively supporting its activation are two very different things. Things can still take a very different turn from here on out.
Where Do We Go From Here After Locking in BIP91?
Locking in BIP91 was an enormous feat. It required over 80% of the total hashpower to signal intent for this solution, and one can safely say the mining pools and community came together for the greater good. At the same time, this was only a small victory in a lengthy war and things are not set in stone.
With the lock-in secured, the Bitcoin network is now in a grace period. There will be a period of time until non-SegWit blocks are rejected by the network. This is a big change, even though the majority of the network is seeming to signal SegWit blocks. SegWit2x and USF signals are both considered “valid,” whereas pools or miners signaling Bitcoin Unlimited, for example, will see their blocks rejected. This rejection period will go into effect very soon.
Despite all of this positive momentum, there is no guarantee for a successful SegWit activation. It could be activated instead as BIP141. While BIP91 signals intent to support BIP141’s SegWit, it is merely based on hashpower. If mining pools and miners were to pull out suddenly, there would be nothing anyone could do to prevent it. Considering how very few economic nodes support BIP91 right now, it seems unlikely we will see a “pure” activation of Segregated Witness.
If the majority of miners changed their mind, they would risk being forked off the main Bitcoin blockchain. That would result in the chain split people are so desperately trying to avoid. BIP91 was introduced to make SegWit2x and the UASF compatible to avoid a chain split. However, it could end up being the catalyst for an actual network split, which is still a possible outcome at this stage.
For the time being, there is no evidence to suggest that miners would suddenly turn their backs on BIP91. However, just because this small milestone has been reached does not mean everything will be smooth sailing. The miners will follow the largest chain, regardless of whether or not it supports “pure” Segregated Witness. It also means the minority supporting the BIP91 soft fork can be ignored by the rest of the network in a few weeks from now.
This “public intent to signal for something” is nothing more than an empty promise by miners and mining pools. Now is the time for these individuals to put their money where their mouth is and make Bitcoin scale properly, regardless of political shenanigans. Assuming things remain as they are now, we will see the first steps toward activating SegWit in about a week’s time.