From: Alex Kotenko <alexykot@gmail•com>
To: Andreas Schildbach <andreas@schildbach•de>
Cc: Bitcoin Dev <bitcoin-development@lists•sourceforge.net>
Subject: Re: [Bitcoin-development] Payment Protocol for Face-to-face Payments
Date: Fri, 21 Mar 2014 13:54:25 +0000 [thread overview]
Message-ID: <CALDj+Bb=CR1pL0Ze1M6k22wfQM1bL6-w+EyipJQWc1OHhAY0rg@mail.gmail.com> (raw)
In-Reply-To: <lgh1q8$1dc$1@ger.gmane.org>
[-- Attachment #1: Type: text/plain, Size: 3740 bytes --]
2014-03-21 9:47 GMT+00:00 Andreas Schildbach <andreas@schildbach•de>:
> On 03/20/2014 05:14 PM, Alex Kotenko wrote:
>
> > Hmm, if we're inventing an URI for bluetooth, I'd rather follow existing
> > URI's patterns. BT is strictly point-to-point connection, so BT MAC
> > should be considered as server address, and payment request ID can be
> > considered as request path. Probably "bt:<bt-mac>/
> > <random_id_of_payment_request>" would be more usual and easily
> > understandable.
>
> Agreed. I used the dash because I feared a slash would need to be
> escaped if used in an URL parameter.
>
It will need to be escaped, but HTTP URLs used in BIP72 have it already,
so don't see why we should bother.
> > I wonder how complex it would be to implement HTTP-over-Bluetooth. Not
> > like I'm willing to do that now, but HTTP is well known and proven to be
> > quite good for tasks like this, so in theory it would be handy to have
> > such capacities in here.
>
> Thought of that as well. On the other hand, HTTP might be overkill and
> we inherit its potential downsides as well.
>
It definitely is an overkill. Don't think we should do it now unless we
will see later during implementation that we really have to.
> > Well, do we need to be compatible? If the dev community decides
> Base43
> > PR QR's (or whatever other self-contained format) is the way to go,
> we
> > just implement, roll it out and use it.
> >
> > My PoS needs to be compatible with BIP21, as when I'm presenting QR code
> > or sending NFC message - I have no way to tell what wallet/phone is on
> > the accepting side, so I have to be compatible to existing widely
> > supported technologies.
>
> Agreed. All I wanted to say support for QR is still small enough that we
> might be able to switch to an incompatible standard. If we're determined
> that is.
Ok. Btw, I've tested QR possibilities on my PoS screen, in binary mode
it's limited to about 600 chars, so really I can include only unsigned and
rather short payment request. Signed requests longer than few hundred bytes
will not work.
> > Well, yes, it would be less efficient than base43. But did you
> > calculate how much less? It's a compatible and already widely used way
> > and loosing compatibility needs to have serious reasons, so would be
> > great to know exact figures here.
>
> Base 64 via binary QR: 64 chars / 256 chars
> ==> 6 bit / 8 bit = 0.75
>
> Base 43 via alphanum QR: 43 chars / 45 chars
> ==> 5.43 bit / 5.49 bit = 0.99
>
> That would be efficiency in terms of PR data size vs. amount space used
> in a QR code. Of course, the visual QR encoding also plays a role, for
> example its size is increased in discrete steps.
>
Ok, so base43-aphanum is winning about a quarter of capacity against
base64-binary. I probably will skip this anyway and go with bluetooth URI
scheme we've just agreed + old style payments over p2p network as fallback.
So no payment requests in QR codes at all from my side.
>
>
>
>
> ------------------------------------------------------------------------------
> Learn Graph Databases - Download FREE O'Reilly Book
> "Graph Databases" is the definitive new guide to graph databases and their
> applications. Written by three acclaimed leaders in the field,
> this first edition is now available. Download your free book today!
> http://p.sf.net/sfu/13534_NeoTech
> _______________________________________________
> Bitcoin-development mailing list
> Bitcoin-development@lists•sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/bitcoin-development
>
[-- Attachment #2: Type: text/html, Size: 5649 bytes --]
next prev parent reply other threads:[~2014-03-21 13:55 UTC|newest]
Thread overview: 69+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-01-27 11:59 Andreas Schildbach
2014-01-27 13:11 ` Mike Hearn
2014-01-27 18:18 ` Andreas Schildbach
2014-01-27 18:34 ` Mike Hearn
2014-01-27 20:53 ` [Bitcoin-development] Experiment with linking payment requests via href Andreas Schildbach
2014-01-27 21:47 ` Mike Hearn
2014-01-27 17:11 ` [Bitcoin-development] Payment Protocol for Face-to-face Payments Jeremy Spilman
2014-01-27 17:39 ` Andreas Schildbach
2014-01-27 18:18 ` Jeremy Spilman
2014-01-27 20:34 ` Roy Badami
2014-01-29 14:57 ` Christophe Biocca
2014-01-30 10:46 ` Andreas Schildbach
2014-01-30 10:50 ` Mike Hearn
2014-02-07 23:15 ` Andreas Schildbach
2014-03-02 9:47 ` Andreas Schildbach
2014-03-02 11:50 ` Mike Hearn
2014-03-20 2:22 ` Alex Kotenko
2014-03-20 3:31 ` Jeff Garzik
2014-03-20 8:09 ` Andreas Schildbach
2014-03-20 10:36 ` Mike Hearn
2014-03-20 12:12 ` Adam Back
2014-03-20 12:20 ` Mike Hearn
2014-03-20 17:31 ` Jeff Garzik
2014-03-20 17:42 ` Alex Kotenko
2014-03-20 18:01 ` Jeff Garzik
2014-03-21 10:28 ` Andreas Schildbach
2014-03-21 13:59 ` Alex Kotenko
2014-03-22 16:35 ` Jeff Garzik
2014-03-22 16:45 ` Mike Hearn
2014-03-22 16:55 ` Mark Friedenbach
2014-03-22 17:24 ` Jeff Garzik
2014-03-22 17:30 ` Mike Hearn
2014-03-23 3:47 ` Alex Kotenko
2014-03-21 10:25 ` Andreas Schildbach
2014-03-21 10:59 ` Adam Back
2014-03-21 11:08 ` Mike Hearn
2014-03-21 11:33 ` Mike Hearn
2014-03-21 12:25 ` Adam Back
2014-03-21 13:07 ` Mike Hearn
2014-03-20 18:20 ` Alex Kotenko
2014-03-20 18:31 ` Mike Hearn
2014-03-20 18:50 ` Alex Kotenko
2014-03-20 21:52 ` Roy Badami
2014-03-20 23:02 ` Mike Hearn
2014-03-26 22:48 ` Roy Badami
2014-03-26 22:56 ` Mike Hearn
2014-03-26 23:20 ` Andreas Schildbach
2014-03-27 10:08 ` Mike Hearn
2014-03-27 13:31 ` vv01f
2014-06-30 19:26 ` Alex Kotenko
2014-07-01 8:18 ` Mike Hearn
2014-07-01 9:48 ` Andreas Schildbach
2014-07-01 10:42 ` Michael Wozniak
2014-07-01 13:03 ` Alex Kotenko
2014-07-01 14:59 ` Andreas Schildbach
2014-07-01 15:07 ` Michael Wozniak
2014-07-01 15:39 ` Andreas Schildbach
2014-07-01 17:18 ` Alex Kotenko
2014-07-01 17:59 ` Mike Hearn
2014-07-02 8:49 ` Alex Kotenko
2014-03-21 10:43 ` Andreas Schildbach
2014-03-20 8:08 ` Andreas Schildbach
2014-03-20 16:14 ` Alex Kotenko
2014-03-21 9:47 ` Andreas Schildbach
2014-03-21 13:54 ` Alex Kotenko [this message]
2014-03-21 14:51 ` Andreas Schildbach
2014-03-21 15:38 ` Alex Kotenko
2014-03-21 15:20 ` Andreas Schildbach
2014-03-21 15:24 ` Mike Hearn
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='CALDj+Bb=CR1pL0Ze1M6k22wfQM1bL6-w+EyipJQWc1OHhAY0rg@mail.gmail.com' \
--to=alexykot@gmail$(echo .)com \
--cc=andreas@schildbach$(echo .)de \
--cc=bitcoin-development@lists$(echo .)sourceforge.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox