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From: Ethan Heilman <eth3rs@gmail.com>
Date: Sat, 25 Feb 2017 17:34:38 -0500
Message-ID: <CAEM=y+XEXuf+BPOH0h=Hn3_9PeL4Dv9G3ySN6fe5zH7bJVkSDA@mail.gmail.com>
To: Pieter Wuille <pieter.wuille@gmail.com>, 
	Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>
Content-Type: multipart/alternative; boundary=001a1144f324fe4dfc054962755d
Cc: Steve Davis <steven.charles.davis@gmail.com>
Subject: Re: [bitcoin-dev] SHA1 collisions make Git vulnerable to attakcs by
 third-parties, not just repo maintainers
Precedence: list

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I strongly encourage Bitcoin to move from 80-bit collision resistance
(RIPEMD-160) to 128-bit collision resistance (SHA-256).

On Sat, Feb 25, 2017 at 5:14 PM, Pieter Wuille via bitcoin-dev <
bitcoin-dev@lists.linuxfoundation.org> wrote:

>
>
> On Feb 25, 2017 14:09, "Steve Davis via bitcoin-dev" <bitcoin-dev@lists.
> linuxfoundation.org> wrote:
>
> Hi Peter,
>
>
> I really, really don=E2=80=99t want to get into it but segwit has many as=
pects
> that are less appealing, not least of which being the amount of time it
> would take to reach the critical mass.
>
> Surely there's a number of alternative approaches which could be explored=
,
> even if only to make a fair assessment of a best response?
>
>
> Any alternative to move us away from RIPEMD160 would require:
> * A drafting of a softfork proposal, implementation, testing, review.
> * A new address format
> * Miners accepting the new consensus rules
> * Wallets adopting the new address format, both on the sender side and
> receiver side (which requires new signatures).
>
> I.e., exactly the same as segwit, for which most of these are already
> done. And it would still only apply to wallets adopting it.
>
> --
> Pieter
>
>
> _______________________________________________
> bitcoin-dev mailing list
> bitcoin-dev@lists.linuxfoundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>
>

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<div dir=3D"ltr">I strongly encourage Bitcoin to move from 80-bit collision=
 resistance (RIPEMD-160) to 128-bit collision resistance (SHA-256).</div><d=
iv class=3D"gmail_extra"><br><div class=3D"gmail_quote">On Sat, Feb 25, 201=
7 at 5:14 PM, Pieter Wuille via bitcoin-dev <span dir=3D"ltr">&lt;<a href=
=3D"mailto:bitcoin-dev@lists.linuxfoundation.org" target=3D"_blank">bitcoin=
-dev@lists.linuxfoundation.org</a>&gt;</span> wrote:<br><blockquote class=
=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padd=
ing-left:1ex"><div dir=3D"auto"><div><br><div class=3D"gmail_extra"><br><di=
v class=3D"gmail_quote">On Feb 25, 2017 14:09, &quot;Steve Davis via bitcoi=
n-dev&quot; &lt;<a href=3D"mailto:bitcoin-dev@lists.linuxfoundation.org" ta=
rget=3D"_blank">bitcoin-dev@lists.<wbr>linuxfoundation.org</a>&gt; wrote:<b=
r type=3D"attribution"><blockquote class=3D"m_3862760052525700813quote" sty=
le=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hi Pet=
er,<span class=3D""><br>
<div class=3D"m_3862760052525700813quoted-text"><br></div><div class=3D"m_3=
862760052525700813quoted-text">
<br>
</div>I really, really don=E2=80=99t want to get into it but segwit has man=
y aspects that are less appealing, not least of which being the amount of t=
ime it would take to reach the critical mass.<br>
<br>
Surely there&#39;s a number of alternative approaches which could be explor=
ed, even if only to make a fair assessment of a best response?<br></span></=
blockquote></div></div></div><div dir=3D"auto"><br></div><div dir=3D"auto">=
Any alternative to move us away from RIPEMD160 would require:</div><div dir=
=3D"auto">* A drafting of a softfork proposal, implementation, testing, rev=
iew.</div><div dir=3D"auto">* A new address format</div><div dir=3D"auto">*=
 Miners accepting the new consensus rules</div><div dir=3D"auto">* Wallets =
adopting the new address format, both on the sender side and receiver side =
(which requires new signatures).</div><div dir=3D"auto"><br></div><div dir=
=3D"auto">I.e., exactly the same as segwit, for which most of these are alr=
eady done. And it would still only apply to wallets adopting it.</div><span=
 class=3D"HOEnZb"><font color=3D"#888888"><div dir=3D"auto"><br></div><div =
dir=3D"auto">--=C2=A0</div><div dir=3D"auto">Pieter</div><div dir=3D"auto">=
<br></div><div dir=3D"auto"><div class=3D"gmail_extra"><div class=3D"gmail_=
quote"><blockquote class=3D"m_3862760052525700813quote" style=3D"margin:0 0=
 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"></blockquote></div></d=
iv></div></font></span></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>

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