Subject: Re: [bitcoin-dev] Regarding setting a lower minrelaytxfee

From: Peter Todd <[email-masked]>
Date: Mon, 1 Aug 2022 09:37:47 -0400

On Mon, Aug 01, 2022 at 01:19:05PM +0000, aliashraf.btc At protonmail wrote:
> > On Sat, Jul 30, 2022 at 05:24:35PM +0000, alicexbt via bitcoin-dev wrote:
> > like a hashcash-based alternative broadcast scheme.
> Hi Peter,
> I've been mulling the idea of attaching work to low fee txns, both as a compensation (e.g., in a sidechain, or an alt), and/or as a spam proof. Unfortunately, both suffer from ASICs:
> For spam proof case, the adversary can easily buy a used/obsolete device to produce lots of spam txns very cheaply, unless you put the bar very high, making it almost impossible for average users to even try.
> The compensation scenario is pretty off-topic, still, interesting enough for 1 min read:
> Wallets commit to the latest blockchain state in the transaction AND attach work.
> It is considered contribution to the security (illegitimate chains can't include the txn), hence isrewarded by fee discount/exemption depending on the offset of the state they've committed to (the closer, the better) and the amount of work attached.
> For this to work, block difficulty is calculated inclusive with the work embedded in the txns, it contains. Sophisticated and consequential, yet not infeasible per se.
> 
> Unfortunately, this scheme is hard to balance with ASICs in the scene too, for instance, you can't subsidize wallets for their work like with a leverge, because miners can easily do it locally, seizing the subsidies for themselves, long story, not relevant just ignore it.

We're not talking about a consensus system here. Just a way to rate-limit
access to a broadcast network used by a small minority of nodes. It's
completely ok to simply change the PoW algorithm in the _highly_ unlikely event
someone bothers to build an ASIC for it. Since this isn't a consensu system,
it's totally ok if multiple versions of the scheme run in parallel.

-- 
https://petertodd.org 'peter'[:-1]@petertodd.org