Subject: Re: [bitcoin-dev] A Better MMR Definition

From: Peter Todd <[email-masked]>
Date: Thu, 23 Feb 2017 22:15:31 -0500

On Thu, Feb 23, 2017 at 07:02:36PM -0800, Bram Cohen wrote:
> On Thu, Feb 23, 2017 at 6:58 PM, Peter Todd <[email-masked]> wrote:
> 
> >
> > 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?
> >
> 
> 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 utxo
> 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 commitments.

Secondly, am I correct in saying your UTXO commitments scheme requires random
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 ordering
to be?

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

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