Subject: Re: [Bitcoin-development] Payment Protocol: BIP 70, 71, 72

From: Gavin Andresen <[email-masked]>
Date: Tue, 20 Aug 2013 09:19:38 +1000

On Tue, Aug 20, 2013 at 8:15 AM, Andreas Petersson <[email-masked]>wrote:

> I was just reviewing the integration work to integrate the Payment
> Protocol into our products. Is there any notion of a standardized
> invoice serialisation? If i pay for two Burgers and one Club Mate, how
> would my Bitcoin Wallet be able to know that?

No. There are XML-based (shudder) standards for electronic invoicing that
include all sorts of bells and whistles; the PaymentDetails message could
easily encapsulate one of them in an 'invoice' field extension. Or we could
reinvent the wheel and come up with our own, but I'd rather use an existing
standard (or maybe a subset of an existing standard).

I didn't want to wade into that swamp for the 1.0 version of the payment
protocol.

> Right now, i would simply
> put that into "memo" and come up with my own serialisation mechanism.
>

"Two Burgers, one Club Mate" seems pretty user-friendly.

Second, is there a way to communicate acceptance levels of TX
> (unconfirmed, 1 conf, 6 conf) maybe using several PaymentACK?
>

No, because the Payment->PaymentACK communication round-trip is done in
one, non-persistent http request-response round-trip.

I don't think we want to allow merchants to push messages to the wallet
(wouldn't take long for merchants to use the opportunity to push annoying
advertising at me, I think), and I don't think we want wallets to poll the
merchant. Although maybe a payment protocol version 2.0 feature could be a
PaymentACK extension that says "ask me how the transaction is going at THIS
URL in THIS many minutes."

-- 
--
Gavin Andresen