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Date: Sat, 17 Aug 2013 16:15:31 +0200
Message-ID: <CAPg+sBhHmXx_qV7i-9rSBHsV7U7AET7b+FXecRuROMF=R2UJhA@mail.gmail.com>
From: Pieter Wuille <pieter.wuille@gmail.com>
To: Jeff Garzik <jgarzik@bitpay.com>
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Cc: Bitcoin Dev <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] Combining bloom filters?
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If both constructed bloom filters use the same seed and the same number of
hash functions, yes. Assuming the input filters were optimal for a given FP
rate, the resulting filter will be worse.

-- 
Pieter
 On 17 Aug 2013 16:01, "Jeff Garzik" <jgarzik@bitpay.com> wrote:

> Consider wallet A builds bloom filter A' and wallet B builds bloom
> filter B'.  Can A' and B' be or'd together to form a single bloom
> filter C' ?
>
> --
> Jeff Garzik
> Senior Software Engineer and open source evangelist
> BitPay, Inc.      https://bitpay.com/
>
>
> ------------------------------------------------------------------------------
> Get 100% visibility into Java/.NET code with AppDynamics Lite!
> It's a free troubleshooting tool designed for production.
> Get down to code-level detail for bottlenecks, with <2% overhead.
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> Bitcoin-development@lists.sourceforge.net
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<p dir=3D"ltr">If both constructed bloom filters use the same seed and the =
same number of hash functions, yes. Assuming the input filters were optimal=
 for a given FP rate, the resulting filter will be worse.</p>
<p dir=3D"ltr">-- <br>
Pieter<br>
</p>
<div class=3D"gmail_quote">On 17 Aug 2013 16:01, &quot;Jeff Garzik&quot; &l=
t;<a href=3D"mailto:jgarzik@bitpay.com">jgarzik@bitpay.com</a>&gt; wrote:<b=
r type=3D"attribution"><blockquote class=3D"gmail_quote" style=3D"margin:0 =
0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Consider wallet A builds bloom filter A&#39; and wallet B builds bloom<br>
filter B&#39;. =A0Can A&#39; and B&#39; be or&#39;d together to form a sing=
le bloom<br>
filter C&#39; ?<br>
<br>
--<br>
Jeff Garzik<br>
Senior Software Engineer and open source evangelist<br>
BitPay, Inc. =A0 =A0 =A0<a href=3D"https://bitpay.com/" target=3D"_blank">h=
ttps://bitpay.com/</a><br>
<br>
---------------------------------------------------------------------------=
---<br>
Get 100% visibility into Java/.NET code with AppDynamics Lite!<br>
It&#39;s a free troubleshooting tool designed for production.<br>
Get down to code-level detail for bottlenecks, with &lt;2% overhead.<br>
Download for free and get started troubleshooting in minutes.<br>
<a href=3D"http://pubads.g.doubleclick.net/gampad/clk?id=3D48897031&amp;iu=
=3D/4140/ostg.clktrk" target=3D"_blank">http://pubads.g.doubleclick.net/gam=
pad/clk?id=3D48897031&amp;iu=3D/4140/ostg.clktrk</a><br>
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velopment</a><br>
</blockquote></div>

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