Blockstream Green to Become the Blockstream App

[Pmalek]

This development of theirs gives more importance to the Liquid Network and also to Simplicity smart contracts. That was the idea. The Liquid sidechain isn't trustless like Bitcoin. I don't know about Simplicity, though. But history has shown that some smart contracts were badly developed and created huge problems.

One interesting part of the blog post says that the outputs protected with quantum-resistant Simplicity smart contracts don't cost anything until they are spent. Blockstream and Liquid might be looking to earn money with this.

[dkbit98]

The latest Blockstream desktop version was updated to 3.1.0 a few days ago. You can now receive L-BTC via the Lightning channel or pay Lightning invoices using L-BTC. Another newly added feature enables swapping between BTC and L-BTC.

Aqua wallet added this same feature long time ago, not that I use it.

Blockstream claims that they have deployed a new signature verification scheme that includes protection against quantum computer threats. It's supposedly live on the Liquid network thanks to the Simplicity sidechain, using SHRINCS (optimized hash-based sigs). It should enable protection of Liquid Bitcoin and all other tokens on the Liquid network.

They can do that because it's much easier to change anything on liquid chain, unlike on bitcoin blockchain.
Still I don't think L-BTC on Liquid is safe simply because Liquid is federated blockchain, they can literally change anything they want.

[Pmalek]

They can do that because it's much easier to change anything on liquid chain, unlike on bitcoin blockchain.
Still I don't think L-BTC on Liquid is safe simply because Liquid is federated blockchain, they can literally change anything they want.

That's a compromise that users have to accept if they decide to use liquid bitcoin or any of the other tokens available on that network. Bitcoin is decentralized, but moves at the speed of a snail when it comes to upgrading and voting in new features. Liquid is a more centralized network, but they keep increasing the number of federation members, which is a good thing. The more parties there are, the less chance of a collusion for nefarious purposes.

[internetional]

Blockstream App is a non-custodial and open-source (so they say)

"So they say" is a very appropriate qualification - and not only regarding the open-source claim, but also the claim of being non-custodial. When it comes to holding bitcoin in Lightning Network channels, I would not agree that it is truly non-custodial. At least, Blockstream Green wasn't.

I used Green for Lightning in the past, and at one point I ran into a situation where, after a force-close of a channel, my funds were sent to an address that was not controlled by my seed phrase. Recovering those funds required about five months of back-and-forth with Blockstream support, and most of my messages were simply ignored during that time.

Lightning->Liquid submarine swaps are much safer than direct Lightning channels in Greenlight architecture.

[Forsyth Jones]

On the iPhone app, it's taking a long time to access the wallet after entering the PIN... it shouldn't be like that. I haven't yet checked if it accesses without internet.

Here they explained what they actually did.

They didn’t wait for the relevant Liquid consensus and instead used Simplicity to design custom spending conditions that can be signed with PQ signatures using one of the SHRINCS variants they developed for this purpose.

A smart approach, to say the least.

Although I haven't delved into the subject in detail, it's a good addition to prepare for possible future threats. However, from what I understand, it only benefits assets on the Liquid network, while on Bitcoin it depends on the network's general consensus.
Using Liquid assets is very good, it's a shame that very few exchanges support it.

[mikel_012]

Blockstream claims that they have deployed a new signature verification scheme that includes protection against quantum computer threats. It's supposedly live on the Liquid network thanks to the Simplicity sidechain, using SHRINCS (optimized hash-based sigs). It should enable protection of Liquid Bitcoin and all other tokens on the Liquid network.

https://x.com/blksresearch/status/2029225084876189900

Here they explained what they actually did.

They didn’t wait for the relevant Liquid consensus and instead used Simplicity to design custom spending conditions that can be signed with PQ signatures using one of the SHRINCS variants they developed for this purpose.

A smart approach, to say the least.

But if every liquid Bitcoin is pegged to real Bitcoin, if Bitcoin gets attacked by quantum computers isn't liquid losing the backing and making it useless anyways? I don't understand a lot so about the technical parts of this, so this is a honest question I have

[nc50lc]

-snip-
A smart approach, to say the least.

But if every liquid Bitcoin is pegged to real Bitcoin, if Bitcoin gets attacked by quantum computers isn't liquid losing the backing and making it useless anyways? I don't understand a lot so about the technical parts of this, so this is a honest question I have

The answer is simple: Not every Bitcoin UTXO will be susceptible to quantum computers in the future.
Mostly those that have their public key exposed (e.g.: P2PK or reused addresses) are the ones that can be attacked with a reasonable chance.
And "Peg-in address" aren't recommended to be reused and don't have their pubKeys exposed to the public.

If real-time attack is your concern (e.g.: up to 10minutes average, right after broadcasting the transaction).
I believe Bitcoin should already have implemented some QC-proof scripts by then,
Even before a month-long attack become possible, there should already be QC-proof scripts that they can migrate to.

Not to mention, the attacker must do it 11 times since it requires 11 signatures out of the 15 public keys to spend before the timelock.

[satscraper]

Blockstream claims that they have deployed a new signature verification scheme that includes protection against quantum computer threats. It's supposedly live on the Liquid network thanks to the Simplicity sidechain, using SHRINCS (optimized hash-based sigs). It should enable protection of Liquid Bitcoin and all other tokens on the Liquid network.

https://x.com/blksresearch/status/2029225084876189900

Here they explained what they actually did.

They didn’t wait for the relevant Liquid consensus and instead used Simplicity to design custom spending conditions that can be signed with PQ signatures using one of the SHRINCS variants they developed for this purpose.

A smart approach, to say the least.

But if every liquid Bitcoin is pegged to real Bitcoin, if Bitcoin gets attacked by quantum computers isn't liquid losing the backing and making it useless anyways? I don't understand a lot so about the technical parts of this, so this is a honest question I have

Yeah, you are correct and Blockstream admits this:

Blockstream framed what they did as the " first building block" for PQ resistance

[Pmalek]

But if every liquid Bitcoin is pegged to real Bitcoin, if Bitcoin gets attacked by quantum computers isn't liquid losing the backing and making it useless anyways? I don't understand a lot so about the technical parts of this, so this is a honest question I have

Yes, of course. If the value of the real bitcoin drops drastically against the USD, for example, the same would happen to the value of liquid bitcoin as well. There can't be a situation where BTC goes down to $50k but LBTC goes up to $100k. All wrapped bitcoin tokens would suffer in the same way because the underlying asset's price has gone down.