[bitcoin-dev] BIP0074 Draft (Dynamic Rate Lookup)

["David Barnes | Bitcoin Co. Ltd." <david.barnes@bitcoin.co.th>]

Please take a look at my BIP0074 draft proposal (this is my first one so
may be incorrectly formatted)
https://github.com/bitcoincoltd/bips/blob/master/bip-0074.mediawiki

This proposal will make it possible for a simpler form of Bitcoin
payment at physical shop locations.

Currently when making a Bitcoin payment at a shop the merchant needs to
have an app of some kind so that they can calculate the amount of
bitcoins you need to pay them to cover your purchase (of for example:
$9.99).

The problem is that many employees are not properly trained on the
Bitcoin app, or the owner is the one with the app and he is often not
there.  When visiting "Bitcoin Accepting" estabishments you will often
run into this problem.  The businesses often don't get enough Bitcoin
business to warrant training sessions or dedicate hardware to run the app.

A simpler way to accept payments would be for the merchant to have a
fixed QR code, and no app at all.  However a printed QR code can't
calculate any exchange rates, and so it would be up to the customer to
choose how much to pay.

This can be result in some problems as the customer may be using their
default wallet exchange rates, or their preferred international
exchange. While the merchant may be actually using a local exchange or
service to exchange the coins to local currency, and there may be some
discrepancy between what the customer thinks the rate should be and what
the merchant thinks the rate should be.

Enter BIP0074, so that the merchant can specify which exchange rates
they are using, and the customer and then look up the rates from this
source and pay according to these rates.

David Barnes