Payment codes establish the identity of the payer and allow for simpler
methods for identifying the payee, and automatically provide the payee with
the information they need to send a refund.

If merchants and customers were using payment codes, they would not need
the BIP70 equivalents.

I think the best way to explain payment codes is that they add the missing
"from address" to transactions which users want, but we've had to tell them
they can't have.

A payment code behaves much more like an email address than a traditional
Bitcoin address.

On Sun, Apr 26, 2015 at 2:58 PM, Mike Hearn <mike@plan99.net> wrote:

> Could you maybe write a short bit of text comparing this approach to
> extending BIP70 and combining it with a simple Subspace style
> store-and-forward network?
>