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Date: Mon, 19 Jan 2015 19:16:54 +0000
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From: Richard Brady <rnbrady@gmail.com>
To: Jeff Garzik <jgarzik@bitpay.com>
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Cc: Bitcoin <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] BIP70: why Google Protocol Buffers for
	encoding?
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Fair points, although for me the line is blurred between which of those are
security considerations vs performance considerations.

Richard

On 19 January 2015 at 19:09, Jeff Garzik <jgarzik@bitpay.com> wrote:

> Text formats such as XML or JSON are far less deterministic, are more
> loosely specified, have wide variance in parsing, are not very hash-able,
> the list goes on.
>
>
> On Mon, Jan 19, 2015 at 2:07 PM, Richard Brady <rnbrady@gmail.com> wrote:
>
>> Hi Gavin, Mike and co
>>
>> Is there a strong driver behind the choice of Google Protocol Buffers for
>> payment request encoding in BIP-0070?
>>
>> Performance doesn't feel that relevant when you think that:
>> 1. Payment requests are not broadcast, this is a request / response flow,
>> much more akin to a web request.
>> 2. One would be cramming this data into a binary format just so you can
>> then attach it to a no-so-binary format such as HTTP.
>>
>> Some great things about protocols/encodings such as HTTP/JSON/XML are:
>> 1. They are human readable on-the-wire. No Wireshark plugin required,
>> tcpdump or ngrep will do.
>> 2. There are tons of great open source libraries and API for parsing /
>> manipulating / generating.
>> 3. It's really easy to hand-craft a test message for debugging.
>> 4. The standards are much easier to read and write. They don't need to
>> contain code like BIP-0070 currently does and they can contain examples,
>> which BIP70 does not.
>> 5. They are thoroughly specified by independent standards bodies such as
>> the IETF. Gotta love a bit of MUST / SHOULD / MAY in a standard.
>> 6. They're a family ;-)
>>
>> Keen to hear your thoughts on this and very keen to watch the payment
>> protocol grow regardless of encoding choice! My background is SIP / VoIP
>> and I think that could be a fascinating use case for this protocol which
>> I'm hoping to do some work on.
>>
>> Best,
>> Richard
>>
>>

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<div dir=3D"ltr"><div class=3D"gmail_extra">Fair points, although for me th=
e line is blurred between which of those are security considerations vs per=
formance considerations.</div><div class=3D"gmail_extra"><br></div><div cla=
ss=3D"gmail_extra">Richard</div><div class=3D"gmail_extra"><br><div class=
=3D"gmail_quote">On 19 January 2015 at 19:09, Jeff Garzik <span dir=3D"ltr"=
>&lt;<a href=3D"mailto:jgarzik@bitpay.com" target=3D"_blank">jgarzik@bitpay=
.com</a>&gt;</span> wrote:<br><blockquote class=3D"gmail_quote" style=3D"ma=
rgin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir=3D"lt=
r">Text formats such as XML or JSON are far less deterministic, are more lo=
osely specified, have wide variance in parsing, are not very hash-able, the=
 list goes on.<br><br></div><div class=3D"gmail_extra"><br><div class=3D"gm=
ail_quote"><div><div>On Mon, Jan 19, 2015 at 2:07 PM, Richard Brady <span d=
ir=3D"ltr">&lt;<a href=3D"mailto:rnbrady@gmail.com" target=3D"_blank">rnbra=
dy@gmail.com</a>&gt;</span> wrote:<br></div></div><blockquote class=3D"gmai=
l_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left=
:1ex"><div><div><div dir=3D"ltr">Hi Gavin, Mike and co<div><br></div><div>I=
s there a strong driver behind the choice of Google Protocol Buffers for pa=
yment request encoding in BIP-0070?</div><div><br></div><div>Performance do=
esn&#39;t feel that relevant when you think that:</div><div>1. Payment requ=
ests are not broadcast, this is a request / response flow, much more akin t=
o a web request.</div><div>2. One would be cramming this data into a binary=
 format just so you can then attach it to a no-so-binary format such as HTT=
P.=C2=A0</div><div><br></div><div>Some great things about protocols/encodin=
gs such as HTTP/JSON/XML are:</div><div>1. They are human readable on-the-w=
ire. No Wireshark plugin required, tcpdump or ngrep will do.</div><div>2. T=
here are tons of great open source libraries and API for parsing / manipula=
ting / generating.</div><div>3. It&#39;s really easy to hand-craft a test m=
essage for debugging.<br></div><div>4. The standards are much easier to rea=
d and write. They don&#39;t need to contain code like BIP-0070 currently do=
es and they can contain examples, which BIP70 does not.=C2=A0</div><div>5. =
They are thoroughly specified by independent standards bodies such as the I=
ETF. Gotta love a bit of MUST / SHOULD / MAY in a standard.</div><div>6. Th=
ey&#39;re a family ;-)</div><div><br></div><div>Keen to hear your thoughts =
on this and very keen to watch the payment protocol grow regardless of enco=
ding choice! My background is SIP / VoIP and I think that could be a fascin=
ating use case for this protocol which I&#39;m hoping to do some work on.</=
div><div><br></div><div>Best,</div><div>Richard</div><div><br></div></div><=
/div></div></blockquote></div></div></blockquote></div></div></div>

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