Subject: Re: [bitcoin-dev] Pre BIP: Solving for spam and other abuse with an HTLB

From: ZmnSCPxj <[email-masked]>
Date: Mon, 18 Mar 2019 04:22:52 +0000

Funding Transaction Pattern is how I name it; I am unaware if this pattern has been named before.
I know gmax created Taproot precisely as an optimization of this pattern, so I presume he is aware of it, and might know a proper name for such.
It is massively ambiguous to call it "gmax technique" as that name could apply to many, many techniques.

Regards,
ZmnSCPxj

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‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
On Monday, March 18, 2019 12:11 AM, Alistair Mann <[email-masked]> wrote:

> Many thanks for your thoughts, ZmnSCPxj.
>
> > I believe there is indeed an important usecase for HTLB over HTLC, which is
> > to improve the anonymity set. An HTLB over HTLC would be indistinguishable
> > onchain from other uses of HTLC; assuming that HTLCs have other uses, this
> > is a (small?) plus to privacy.
> > Note that the redundant <digest> would have to be given by Alice to Bob,
> > since using a standardized one will also reveal use of HTLB over HTLC
> > instead of hiding it among other HTLC UTXOs.
>
> Both these are good observations and I'll act on them.
>
> > Another thing to improve privacy would be to apply the Funding Transaction
> > pattern: https://zmnscpxj.github.io/offchain/generalized.html
>
> <snip>
>
> I've not read of the FTP before; I welcome it, and take on board that it
> improves privacy by keeping a script offline. My first thought is that doesn't
> affect the suggested BIP, so my next update here won't include it. I recognise
> it would improve mainnet use of scripts though, so do expect to return to it.
>
> Cheers,
>
> --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
>
> Alistair Mann