On Wed, Jun 10, 2015 at 2:03 PM, Peter Todd <pete@petertodd.org> wrote:

On Wed, Jun 10, 2015 at 02:00:27PM -0600, Nathan Wilcox wrote:
> On Wed, Jun 10, 2015 at 1:19 PM, Aaron Voisine <voisine@gmail.com> wrote:
>
> > It could be done by agreeing on a data format and encoding it in an
> > op_return output in the coinbase transaction. If it catches on it could
> > later be enforced with a soft fork.
> >
> >
> Sounds plausible, except SPV protocols would need to include this coinbase
> txn if it's going to help SPV clients. (Until a softfork is activated, SPV
> clients should not rely on this encoding, since until that time the results
> can be fabricated by individual miners.)

Fee stats can always be fabricated by individual miners because fees can
be paid out-of-band.

This is a point I hadn't considered carefully before. I don't understand the marketplace here or why miners would want to move fees outside of explicit inband fees. Implicit in this proposal is that the statistics only cover in-band data, because that's the scope of consensus rules, and thus the proposal is only as useful as the information of in-band fees is useful.

I've also noticed a detracting technical argument given a particular tradeoff:

A Header-PoW-verifying client could still be given all transactions in a recent block, from which it can see the in-band fees directly. The trade-off is the size of those transactions versus the need to alter any consensus rules or do soft forks.

Notice how this trade-off's costs change with maximum block size.

--
'peter'[:-1]@petertodd.org
00000000000000001245bd2f5c99379ee76836227ded9c08324894faabc0d27f

Nathan Wilcox
Least Authoritarian

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