Date: Thu, 23 Feb 2017 22:15:31 -0500
From: Peter Todd <pete@petertodd.org>
To: Bram Cohen <bram@bittorrent.com>
Message-ID: <20170224031531.GA32118@savin.petertodd.org>
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Cc: Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>
Subject: Re: [bitcoin-dev] A Better MMR Definition
Precedence: list


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On Thu, Feb 23, 2017 at 07:02:36PM -0800, Bram Cohen wrote:
> On Thu, Feb 23, 2017 at 6:58 PM, Peter Todd <pete@petertodd.org> wrote:
>=20
> >
> > So to be clear, do you agree or disagree with me that you *can* extract=
 a
> > compact proof from a MMR that a given output is unspent?
> >
>=20
> After wading through your logic on how updates are done, I agree that that
> can be done, but apples to apples compact proofs can also be done in a ut=
xo
> commitment, and proofs of the validity of updates can be done in a utxo
> commitment, so there isn't any performance advantage to all that extra
> complexity.

Glad we're on the same page with regard to what's possible in TXO commitmen=
ts.

Secondly, am I correct in saying your UTXO commitments scheme requires rand=
om
access? While you describe it as a "merkle set", obviously to be merkelized
it'll have to have an ordering of some kind. What do you propose that order=
ing
to be?

Maybe more specifically, what exact values do you propose to be in the set?

--=20
https://petertodd.org 'peter'[:-1]@petertodd.org

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