From: Damian Williamson <willtech@live.com.au>
To: Eric Voskuil <eric@voskuil.org>, Evan Klitzke <evan@eklitzke.org>,
	"Bitcoin Protocol Discussion" <bitcoin-dev@lists.linuxfoundation.org>
Thread-Topic: [bitcoin-dev] feature: Enhance privacy by change obfuscation
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Date: Sun, 1 Apr 2018 14:37:13 +0000
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Subject: Re: [bitcoin-dev] feature: Enhance privacy by change obfuscation
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I note that Electrum v3.0.6 has an option to use multiple change addresses.=
 It is off by default.


Regards,

Damian Williamson

________________________________
From: Eric Voskuil <eric@voskuil.org>
Sent: Monday, 19 March 2018 5:59:28 AM
To: Evan Klitzke; Bitcoin Protocol Discussion
Cc: Damian Williamson
Subject: Re: [bitcoin-dev] feature: Enhance privacy by change obfuscation

> This would be really expensive for the network due to the bloat in UTXO s=
ize, a cost everyone has to pay for.

Without commenting on the merits of this proposal, I=92d just like to corre=
ct this common misperception. There is no necessary additional cost to the =
network from the count of unspent outputs. This perception arises from an i=
mplementation detail of particular node software. There is no requirement f=
or redundant indexing of unspent outputs.

e

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<p style=3D"margin-top:0;margin-bottom:0">I note that Electrum v3.0.6 has a=
n option to use multiple change addresses. It is off by default.</p>
<p style=3D"margin-top:0;margin-bottom:0"><br>
</p>
<p style=3D"margin-top:0;margin-bottom:0">Regards,</p>
<p style=3D"margin-top:0;margin-bottom:0">Damian Williamson<br>
</p>
</div>
<hr style=3D"display:inline-block;width:98%" tabindex=3D"-1">
<div id=3D"divRplyFwdMsg" dir=3D"ltr"><font face=3D"Calibri, sans-serif" st=
yle=3D"font-size:11pt" color=3D"#000000"><b>From:</b> Eric Voskuil &lt;eric=
@voskuil.org&gt;<br>
<b>Sent:</b> Monday, 19 March 2018 5:59:28 AM<br>
<b>To:</b> Evan Klitzke; Bitcoin Protocol Discussion<br>
<b>Cc:</b> Damian Williamson<br>
<b>Subject:</b> Re: [bitcoin-dev] feature: Enhance privacy by change obfusc=
ation</font>
<div>&nbsp;</div>
</div>
<div class=3D"BodyFragment"><font size=3D"2"><span style=3D"font-size:11pt;=
">
<div class=3D"PlainText">&gt; This would be really expensive for the networ=
k due to the bloat in UTXO size, a cost everyone has to pay for.<br>
<br>
Without commenting on the merits of this proposal, I=92d just like to corre=
ct this common misperception. There is no necessary additional cost to the =
network from the count of unspent outputs. This perception arises from an i=
mplementation detail of particular
 node software. There is no requirement for redundant indexing of unspent o=
utputs.<br>
<br>
e</div>
</span></font></div>
</body>
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