#BitVM and #Drivechain
Discussion
I have concluded they can't easily pronounce Paul's last name, therefore they hate his idea.
Honest question.
I want to understand.
BitVM supporters say that they do not need any change to Bitcoin, and could do things like drivechains.
Drivechain supporters say that a soft fork is needed, a small change, to use some op code, but I guess it will be difficult to convince core developers to merge it or node operators to run it.
Is it true that BitVM can achieve the same thing without a need for Bitcoin soft fork?
If true, it looks promising, right?
Or, if not the same thing but less, what additional capabilities will be unlocked by drivechains that cannot be done with BitVM?
For BitVM it may be possible to simulate some kind of BIP300 Sidechain.
nostr:npub1yxp7j36cfqws7yj0hkfu2mx25308u4zua6ud22zglxp98ayhh96s8c399s may be able to give more details.
I do not think you can build something exactly equivalent to a drivechain using BitVM. We came up with a few ideas for a form of SPV sidechain. I'm not confident that any of them work, but I think we are close. With a few refinements on our initial ideas, we very well might get something workable.
An SPV sidechain is a kind originally proposed in this 2015 whitepaper: https://blockstream.com/sidechains.pdf
They were thought to require a soft fork. Maybe not anymore. In comparison to a drivechain, an SPV drivechain is probably slightly worse. SPV sidechains rely on an assumption that underpins both bitcoin's doublespend protection and bip300's hashrate escrow: the assumption that 51% of miners will not collude to steal.
However, an SPV sidechain, this assumption is implicit (not explicit) and it does not provide the 3 month buffer that drivechain provides. Miners can "quickly" steal from an SPV sidechain but the whitepaper ignores this because it assumes miners will not do that.
To me there is a sense in which that makes an SPV sidechain slightly worse that a drivechain. Still, I'll happily take what I can get. If we can think of a way to do SPV sidechains via BitVM, I'll get for it, but I'll still want drivechains because I think they are still a slight improvement. Maybe like a 4% improvement.
Note: after reviewing the sidechain's whitepaper again, I saw that it does *not* ignore the "miners can steal" problem. It discusses it at considerable depth in section 4.2 and offers 4 possible mitigations. Still, I like how bip300 handles this better.