P2SH addresses support exotic transaction outputs, but not all exotic transactions. This payment protocol can allow for combining multiple outputs. A PaymentRequest for sending money to multiple parties, for example, could not fall back to a single address.


On Wed, Jul 31, 2013 at 5:38 PM, Gavin Andresen <gavinandresen@gmail.com> wrote:
On Thu, Aug 1, 2013 at 9:30 AM, E willbefull <ewillbefull@gmail.com> wrote:
> I think it's important to expect PaymentRequest-only bitcoin URIs in the
> future. Some types of payments (exotic transactions) may not make sense to
> have a single fallback address.

P2SH addresses already support all exotic transactions.

> Or, a page with a bitcoin URI link may be
> relying on a separate service provider to assemble the transaction.

Do you mean assemble the PaymentRequest message?  Because the payment
transaction will always be created by the customer's wallet software.

IF PaymentRequests take over the world and we get 100% wallet software
support, then I'd be happy to write another BIP that says that a
bitcoin: URI can be just bitcoin:?request=http...

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Gavin Andresen