The BIP70 protocol would preclude individuals from utilizing the P2P transfer spec. It would also require that a Sender have internet connectivity to get the payment protocol info. BLE could enable payment w/o internet by first transferring the URI to from Recipient to Sender. Then in the future, we could sign a Tx and send it over BLE back to the recipient (who would still need internet to verify the Tx). This is an important use case for areas with poor 3G/4G connectivity as I've experience myself.

Also, due to Android issues, NFC is incredibly clunky. The URI Sender is required to tap the screen *while* the two phones are in contact. We support NFC the same way Bitcoin Wallet does, but unless the payment recipient has a custom Android device (which a merchant might) then the usage model is worse than scanning a QR code. BLE also allows people to pay at a distance such as for a donation to a live performer. We'll look at adding this to the Motivation section.

Paul Puey CEO / Co-Founder, Airbitz Inc

+1-619-850-8624 | http://airbitz.co | San Diego

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From: Andreas Schildbach <andreas@sc...> - 2015-02-05 13:47:04

Thanks Paul, for writing up your protocol!

First thoughts:

For a BIP standard, I think we should skip "bitcoin:" URIs entirely and
publish BIP70 payment requests instead. URIs mainly stick around because
of QR codes limited capacity. BIP70 would partly address the "copycat"
problem by signing payment requests.

In your Motivation section, I miss some words about NFC. NFC already
addresses all of the usability issues mentioned and is supported by
mobile wallets since 2011. That doesn't mean your method doesn't make
sense in some situations, but I think it should be explained why to
prefer broadcasting payment requests over picking them up via near field
radio.