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Date: Wed, 8 Jan 2014 23:29:15 +0100
Message-ID: <CAP63atasCa50ts4EWyh8j+ZL4CgCci-9r5WS5CEDqM51iu5E9w@mail.gmail.com>
From: =?ISO-8859-1?Q?Cl=E9ment_Elbaz?= <clem.ds@gmail.com>
To: bitcoin-development@lists.sourceforge.net
Content-Type: multipart/alternative; boundary=047d7b5db124dd90d504ef7d0548
Subject: Re: [Bitcoin-development] Getting trusted metrics from the block
 chain in an untrusted environment ?
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Hello all,

It seems there was a problem with my first email (thank you Mark for the
heads up), so I'll copy paste it there :

-----------------------
Hello all,

I'm designing a program that needs some metrics computed from the Bitcoin
block chain (some address balances, or the occurrence or not of a specific
transaction). The kind of infos you get from http://blockchain.info/,
provided you trust this website (my program do not).

My program should run on lightweight/embedded hardware. The execution
environment provides access to the Bitcoin network but not enough resources
to set up a trusted node along with my program. Also, my program trusts the
global Bitcoin network but no individual node.

I would need a way to ask an untrusted Bitcoin node to compute some 'metric
request' on my behalf and having the result of that metric request
validated by the network.

Is there any available or work-in-progress projects that would come close
to this need ? Or should I do it myself ? :-)

Thank you all,

Cl=E9ment Elbaz

-----------------------


On Wed, Jan 8, 2014 at 8:44 PM, Cl=E9ment Elbaz <clem.ds@gmail.com> wrote:

> Some more thoughts :
>
> If no such project exist yet, I thought it could work with an alternate,
> small and fixed-length 'metric request block chain' of some sort.
>
> It would temporarily stores structures defined as [metric request |
> current block number when request was made | hash of the response] instea=
d
> of financial transactions.
>
> These structures are verifiable so it could work the same way as a regula=
r
> financial blochchain.
>
> It should not be part of the main Bitcoin protocol but could be a plugin
> interacting with the data managed by the fullnode bitcoin software.
>
> Also, metrics requests can be expensive to compute and validate, so it
> would make sense to pay a fee everytime you ask one.
>
> Does any of this makes any sense to you ?
>
> Thanks,
>
> Cl=E9ment
>


--=20
Cl=E9ment ELBAZ
06. 09. 55. 78. 41
clem.ds@gmail.com

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<div dir=3D"ltr"><div>Hello all,<br><br></div>It seems there was a problem =
with my first email (thank you Mark for the heads up), so I&#39;ll copy pas=
te it there :<br><br>-----------------------<br>Hello all,<br><br>I&#39;m d=
esigning a program that needs some metrics=20
computed from the Bitcoin block chain (some address balances, or the=20
occurrence or not of a specific transaction). The kind of infos you get=20
from <a href=3D"http://blockchain.info/" target=3D"_blank">http://blockchai=
n.info/</a>, provided you trust this website (my program do not).<br>
<br>My program should run on lightweight/embedded hardware. The=20
execution environment provides access to the Bitcoin network but not=20
enough resources to set up a trusted node along with my program. Also,=20
my program trusts the global Bitcoin network but no individual node.<br>
<br>I would need a way to ask an untrusted Bitcoin node to compute some=20
&#39;metric request&#39; on my behalf and having the result of that metric=
=20
request validated by the network.<br><br>Is there any available or work-in-=
progress projects that would come close to this need ? Or should I do it my=
self ? :-)<br>
<br>Thank you all,<br><br>Cl=E9ment Elbaz<br><br>-----------------------<br=
></div><div class=3D"gmail_extra"><br><br><div class=3D"gmail_quote">On Wed=
, Jan 8, 2014 at 8:44 PM, Cl=E9ment Elbaz <span dir=3D"ltr">&lt;<a href=3D"=
mailto:clem.ds@gmail.com" target=3D"_blank">clem.ds@gmail.com</a>&gt;</span=
> wrote:<br>
<blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1p=
x #ccc solid;padding-left:1ex"><div dir=3D"ltr">Some more thoughts :<br><br=
>If no such project exist yet, I thought it could work with an alternate, s=
mall and fixed-length &#39;metric request block chain&#39; of some sort. <b=
r>
<br>It would temporarily stores structures defined as [metric request | cur=
rent block number when request was made | hash of the response] instead of =
financial transactions. <br>
<br>These structures are verifiable so it could work the same way as a regu=
lar financial blochchain.<br><br>It should not be part of the main Bitcoin =
protocol but could be a plugin interacting with the data managed by the ful=
lnode bitcoin software.<br>

<br>Also, metrics requests can be expensive to compute and validate, so it =
would make sense to pay a fee everytime you ask one.<br><br>Does any of thi=
s makes any sense to you ?<br><br>Thanks,<br><br>Cl=E9ment</div>
</blockquote></div><br><br clear=3D"all"><br>-- <br>Cl=E9ment ELBAZ<br>06. =
09. 55. 78. 41<br><a href=3D"mailto:clem.ds@gmail.com" target=3D"_blank">cl=
em.ds@gmail.com</a><br>
</div>

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