From: John Hardy <john@seebitcoin.com>
To: Marcel Jamin <marcel@jamin.net>, "bitcoin-dev@lists.linuxfoundation.org"
	<bitcoin-dev@lists.linuxfoundation.org>
Thread-Topic: [bitcoin-dev] Unique node identifiers
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Date: Sun, 5 Mar 2017 12:55:27 +0000
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Subject: Re: [bitcoin-dev] Unique node identifiers
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> Wouldn't this actually *need* to be a bitcoin address that is included in=
 a block

I think it being a bitcoin address probably makes the most sense. The addre=
ss could even be used for donations to incentivise identifier use.

I had not really envisaged this having any blockchain presence though. It w=
as just an easy way to give third party node monitors like coin.dance and b=
itnodes.21.co a few more metrics.

That said, it would allow the creation of a 'nodepool', where each node cou=
ld broadcast its latest status like a transaction, and every node has a reg=
ister of active nodes. Like a mempool, but for nodes.

By leveraging the randomness of node identities, it could be that a determi=
nistic subset of nodes randomly check that a new node status update is legi=
timate by querying the node directly (a small enough subset to not cause a =
DDOS). If a threshhold of those random checking nodes reports that the node=
 either doesn't exist or is responding with conflicting information, this w=
ill become evident to the network and can be flagged.

This should paint a pretty accurate picture of the state of the network, an=
d might also prove useful for developing lightning routing?

________________________________
From: Marcel Jamin <marcel@jamin.net>
Sent: Sunday, March 5, 2017 6:29 AM
To: John Hardy; Bitcoin Protocol Discussion
Subject: Re: [bitcoin-dev] Unique node identifiers

> This could even come in the form of a Bitcoin address.

Wouldn't this actually *need* to be a bitcoin address that is included in a=
 block to get any real assurances about the age if this node id? Otherwise =
malicous nodes could lie and claim to have seen a brand new node id years a=
go already.

Even if included in a block, people could sell their aged IDs (if we were t=
o rely on those for anything).

Also funding that ID address would might tie your economic activity (or eve=
n identity) to a node.

On 4 March 2017 at 17:04, John Hardy via bitcoin-dev <bitcoin-dev@lists.lin=
uxfoundation.org<mailto:bitcoin-dev@lists.linuxfoundation.org>> wrote:

The discussion of UASF got me thinking about whether such a method might le=
ad to sybil attacks, with new nodes created purely to inflate the node coun=
t for a particular implementation in an attempt at social engineering.


I had an idea for an anonymous, opt-in, unique node identification mechanis=
m to help counter this.


This would give every node the opportunity to create a node =91address=92/u=
nique identifier. This could even come in the form of a Bitcoin address.


The node on first installation generates and backs up a private key. The co=
rresponding public key becomes that node=92s unique identifier. If the node=
 switches to a new software version or a new IP, the identifier can remain =
constant if the node operator chooses.


Asking a node for its identifier can be done by sending a message the comma=
nd =91identify=92 and a challenge. The node can then respond with its uniqu=
e identifier and a signature for the challenge to prove it. The node can al=
so include what software it is running and sign this information so it can =
be verified as legitimate by third parties.


Why would we do this?


Well, it adds a small but very useful piece of data when compiling lists of=
 active nodes.


Any register of active nodes can have a record of when a node identifier wa=
s =93first seen=94, and how many IPs the same identifier has broadcast from=
. Also, crucially, we could see what software the node operator has been se=
en running historically.


This information would make it easy to identify patterns. For example if a =
huge new group of nodes appeared on the network with no history for their i=
dentifier they could likely be dismissed as sybil attacks. If a huge number=
 of nodes that had been reporting as Bitcoin Core for an extended period of=
 time started switching to a rival implementation, this would add credibili=
ty but not certainty (keys could be traded), that the shift was more organi=
c.


This would be trivial to implement, is (to me?) non-controversial, and woul=
d give a way for a node to link itself to a pseudo-anonymous identity, but =
with the freedom to opt-out at any time.


Keen to hear any thoughts?


Thanks,


John Hardy

john@seebitcoin.com<mailto:john@seebitcoin.com>

_______________________________________________
bitcoin-dev mailing list
bitcoin-dev@lists.linuxfoundation.org<mailto:bitcoin-dev@lists.linuxfoundat=
ion.org>
https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev



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<html>
<head>
<meta http-equiv=3D"Content-Type" content=3D"text/html; charset=3DWindows-1=
252">
<style type=3D"text/css" style=3D"display:none;"><!-- P {margin-top:0;margi=
n-bottom:0;} --></style>
</head>
<body dir=3D"ltr">
<div id=3D"divtagdefaultwrapper" dir=3D"ltr" style=3D"font-size:12pt; color=
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<div id=3D"divtagdefaultwrapper" dir=3D"ltr" style=3D"font-size:12pt; color=
:#000000; font-family:Calibri,Arial,Helvetica,sans-serif">
<p>&gt;&nbsp;<span style=3D"font-family:arial; font-size:14.6667px; white-s=
pace:pre-wrap">Wouldn't this actually *need* to be a bitcoin address that i=
s included in a block</span></p>
<br>
I think it being a bitcoin address probably makes the most sense. The addre=
ss could even be used for donations to incentivise identifier use.</div>
<div id=3D"divtagdefaultwrapper" dir=3D"ltr" style=3D"font-size:12pt; color=
:#000000; font-family:Calibri,Arial,Helvetica,sans-serif">
<br>
</div>
<div id=3D"divtagdefaultwrapper" dir=3D"ltr" style=3D"font-size:12pt; color=
:#000000; font-family:Calibri,Arial,Helvetica,sans-serif">
I had not really envisaged this having any blockchain presence though. It w=
as just an easy way to give third party node monitors like coin.dance and b=
itnodes.21.co a few more metrics.</div>
<div id=3D"divtagdefaultwrapper" dir=3D"ltr" style=3D"font-size:12pt; color=
:#000000; font-family:Calibri,Arial,Helvetica,sans-serif">
<br>
</div>
<div id=3D"divtagdefaultwrapper" dir=3D"ltr" style=3D"font-size:12pt; color=
:#000000; font-family:Calibri,Arial,Helvetica,sans-serif">
That said, it would allow the creation of a 'nodepool', where each node cou=
ld broadcast its latest status like a transaction, and every node has a reg=
ister of active nodes. Like a mempool, but for nodes.</div>
<div id=3D"divtagdefaultwrapper" dir=3D"ltr" style=3D"font-size:12pt; color=
:#000000; font-family:Calibri,Arial,Helvetica,sans-serif">
<br>
</div>
<div id=3D"divtagdefaultwrapper" dir=3D"ltr" style=3D"font-size:12pt; color=
:#000000; font-family:Calibri,Arial,Helvetica,sans-serif">
<div>By leveraging the randomness of node identities, it could be that a de=
terministic subset of nodes randomly check that a new node status update is=
 legitimate by querying the node directly (a small enough subset to not cau=
se a DDOS). If a threshhold of those
 random checking nodes reports that the node either doesn't exist or is res=
ponding with conflicting information, this will become evident to the netwo=
rk and can be flagged.</div>
<div><br>
</div>
<div>This should paint a pretty accurate picture of the state of the networ=
k, and might also prove useful for developing lightning routing?</div>
<br>
<div style=3D"color:rgb(0,0,0)">
<hr tabindex=3D"-1" style=3D"display:inline-block; width:98%">
<div id=3D"divRplyFwdMsg" dir=3D"ltr"><font face=3D"Calibri, sans-serif" co=
lor=3D"#000000" style=3D"font-size:11pt"><b>From:</b> Marcel Jamin &lt;marc=
el@jamin.net&gt;<br>
<b>Sent:</b> Sunday, March 5, 2017 6:29 AM<br>
<b>To:</b> John Hardy; Bitcoin Protocol Discussion<br>
<b>Subject:</b> Re: [bitcoin-dev] Unique node identifiers</font>
<div>&nbsp;</div>
</div>
<div>
<div dir=3D"ltr">
<div class=3D"gmail_default" style=3D"font-family:monospace,monospace; font=
-size:small; color:rgb(12,52,61)">
&gt;&nbsp;<span style=3D"color:rgb(0,0,0); font-family:arial; font-size:14.=
6667px; white-space:pre-wrap">This could even come in the form of a Bitcoin=
 address.</span></div>
<div class=3D"gmail_default" style=3D"font-family:monospace,monospace; font=
-size:small; color:rgb(12,52,61)">
<span style=3D"color:rgb(0,0,0); font-family:arial; font-size:14.6667px; wh=
ite-space:pre-wrap"><br>
</span></div>
<div class=3D"gmail_default" style=3D"font-family:monospace,monospace; font=
-size:small; color:rgb(12,52,61)">
<span style=3D"color:rgb(0,0,0); font-family:arial; font-size:14.6667px; wh=
ite-space:pre-wrap">Wouldn't this actually *need* to be a bitcoin address t=
hat is included in a block to get any real assurances about the age if this=
 node id? Otherwise malicous nodes
 could lie and claim to have seen a brand new node id years ago already.</s=
pan></div>
<div class=3D"gmail_default" style=3D"font-family:monospace,monospace; font=
-size:small; color:rgb(12,52,61)">
<span style=3D"color:rgb(0,0,0); font-family:arial; font-size:14.6667px; wh=
ite-space:pre-wrap"><br>
</span></div>
<div class=3D"gmail_default" style=3D"font-family:monospace,monospace; font=
-size:small; color:rgb(12,52,61)">
<span style=3D"color:rgb(0,0,0); font-family:arial; font-size:14.6667px; wh=
ite-space:pre-wrap">Even if included in a block, people could sell their ag=
ed IDs (if we were to rely on those for anything).</span></div>
<div class=3D"gmail_default" style=3D"font-family:monospace,monospace; font=
-size:small; color:rgb(12,52,61)">
<span style=3D"color:rgb(0,0,0); font-family:arial; font-size:14.6667px; wh=
ite-space:pre-wrap"><br>
</span></div>
<div class=3D"gmail_default" style=3D"font-family:monospace,monospace; font=
-size:small; color:rgb(12,52,61)">
<span style=3D"color:rgb(0,0,0); font-family:arial; font-size:14.6667px; wh=
ite-space:pre-wrap">Also funding that ID address would might tie your econo=
mic activity (or even identity) to a node.</span></div>
</div>
<div class=3D"gmail_extra"><br>
<div class=3D"gmail_quote">On 4 March 2017 at 17:04, John Hardy via bitcoin=
-dev <span dir=3D"ltr">
&lt;<a href=3D"mailto:bitcoin-dev@lists.linuxfoundation.org" target=3D"_bla=
nk">bitcoin-dev@lists.linuxfoundation.org</a>&gt;</span> wrote:<br>
<blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex; border-left:1=
px #ccc solid; padding-left:1ex">
<div dir=3D"ltr">
<div id=3D"m_4495502098626100444divtagdefaultwrapper" dir=3D"ltr" style=3D"=
font-size:12pt; color:#000000; font-family:Calibri,Arial,Helvetica,sans-ser=
if">
<p><span id=3D"m_4495502098626100444docs-internal-guid-1be5245f-9a0e-19aa-b=
d44-cdeb0d05121c"></span></p>
<p dir=3D"ltr" style=3D"line-height:1.38; margin-top:0pt; margin-bottom:0pt=
"><span style=3D"font-size:11pt; font-family:Arial; background-color:transp=
arent; vertical-align:baseline; white-space:pre-wrap">The discussion of UAS=
F got me thinking about whether such a
 method might lead to sybil attacks, with new nodes created purely to infla=
te the node count for a particular implementation in an attempt at social e=
ngineering.</span></p>
<br>
<p dir=3D"ltr" style=3D"line-height:1.38; margin-top:0pt; margin-bottom:0pt=
"><span style=3D"font-size:11pt; font-family:Arial; background-color:transp=
arent; vertical-align:baseline; white-space:pre-wrap">I had an idea for an =
anonymous, opt-in, unique node identification
 mechanism to help counter this.</span></p>
<br>
<p dir=3D"ltr" style=3D"line-height:1.38; margin-top:0pt; margin-bottom:0pt=
"><span style=3D"font-size:11pt; font-family:Arial; background-color:transp=
arent; vertical-align:baseline; white-space:pre-wrap">This would give every=
 node the opportunity to create a node
 =91address=92/unique identifier. This could even come in the form of a Bit=
coin address.</span></p>
<br>
<p dir=3D"ltr" style=3D"line-height:1.38; margin-top:0pt; margin-bottom:0pt=
"><span style=3D"font-size:11pt; font-family:Arial; background-color:transp=
arent; vertical-align:baseline; white-space:pre-wrap">The node on first ins=
tallation generates and backs up a private
 key. The corresponding public key becomes that node=92s unique identifier.=
 If the node switches to a new software version or a new IP, the identifier=
 can remain constant if the node operator chooses.</span></p>
<br>
<p dir=3D"ltr" style=3D"line-height:1.38; margin-top:0pt; margin-bottom:0pt=
"><span style=3D"font-size:11pt; font-family:Arial; background-color:transp=
arent; vertical-align:baseline; white-space:pre-wrap">Asking a node for its=
 identifier can be done by sending a message
 the command =91identify=92 and a challenge. The node can then respond with=
 its unique identifier and a signature for the challenge to prove it. The n=
ode can also include what software it is running and sign this information =
so it can be verified as legitimate
 by third parties.</span></p>
<br>
<p dir=3D"ltr" style=3D"line-height:1.38; margin-top:0pt; margin-bottom:0pt=
"><span style=3D"font-size:11pt; font-family:Arial; background-color:transp=
arent; vertical-align:baseline; white-space:pre-wrap">Why would we do this?=
</span></p>
<br>
<p dir=3D"ltr" style=3D"line-height:1.38; margin-top:0pt; margin-bottom:0pt=
"><span style=3D"font-size:11pt; font-family:Arial; background-color:transp=
arent; vertical-align:baseline; white-space:pre-wrap">Well, it adds a small=
 but very useful piece of data when compiling
 lists of active nodes.</span></p>
<br>
<p dir=3D"ltr" style=3D"line-height:1.38; margin-top:0pt; margin-bottom:0pt=
"><span style=3D"font-size:11pt; font-family:Arial; background-color:transp=
arent; vertical-align:baseline; white-space:pre-wrap">Any register of activ=
e nodes can have a record of when a node
 identifier was =93first seen=94, and how many IPs the same identifier has =
broadcast from. Also, crucially, we could see what software the node operat=
or has been seen running historically.</span></p>
<br>
<p dir=3D"ltr" style=3D"line-height:1.38; margin-top:0pt; margin-bottom:0pt=
"><span style=3D"font-size:11pt; font-family:Arial; background-color:transp=
arent; vertical-align:baseline; white-space:pre-wrap">This information woul=
d make it easy to identify patterns. For
 example if a huge new group of nodes appeared on the network with no histo=
ry for their identifier they could likely be dismissed as sybil attacks. If=
 a huge number of nodes that had been reporting as Bitcoin Core for an exte=
nded period of time started switching
 to a rival implementation, this would add credibility but not certainty (k=
eys could be traded), that the shift was more organic.</span></p>
<br>
<p dir=3D"ltr" style=3D"line-height:1.38; margin-top:0pt; margin-bottom:0pt=
"><span style=3D"font-size:11pt; font-family:Arial; background-color:transp=
arent; vertical-align:baseline; white-space:pre-wrap">This would be trivial=
 to implement, is (to me?) non-controversial,
 and would give a way for a node to link itself to a pseudo-anonymous ident=
ity, but with the freedom to opt-out at any time.</span></p>
<br>
<p dir=3D"ltr" style=3D"line-height:1.38; margin-top:0pt; margin-bottom:0pt=
"><span style=3D"font-size:11pt; font-family:Arial; background-color:transp=
arent; vertical-align:baseline; white-space:pre-wrap">Keen to hear any thou=
ghts?</span></p>
<br>
<p dir=3D"ltr" style=3D"line-height:1.38; margin-top:0pt; margin-bottom:0pt=
"><span style=3D"font-size:11pt; font-family:Arial; background-color:transp=
arent; vertical-align:baseline; white-space:pre-wrap">Thanks,</span></p>
<br>
<p dir=3D"ltr" style=3D"line-height:1.38; margin-top:0pt; margin-bottom:0pt=
"><span style=3D"font-size:11pt; font-family:Arial; background-color:transp=
arent; vertical-align:baseline; white-space:pre-wrap">John Hardy</span></p>
<p dir=3D"ltr" style=3D"line-height:1.38; margin-top:0pt; margin-bottom:0pt=
"><span style=3D"font-size:11pt; font-family:Arial; background-color:transp=
arent; vertical-align:baseline; white-space:pre-wrap"><a href=3D"mailto:joh=
n@seebitcoin.com" target=3D"_blank">john@seebitcoin.com</a></span></p>
<p></p>
</div>
</div>
<br>
______________________________<wbr>_________________<br>
bitcoin-dev mailing list<br>
<a href=3D"mailto:bitcoin-dev@lists.linuxfoundation.org">bitcoin-dev@lists.=
<wbr>linuxfoundation.org</a><br>
<a href=3D"https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev" =
rel=3D"noreferrer" target=3D"_blank">https://lists.linuxfoundation.<wbr>org=
/mailman/listinfo/bitcoin-<wbr>dev</a><br>
<br>
</blockquote>
</div>
<br>
</div>
</div>
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