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Date: Sat, 18 Jan 2014 15:50:41 -0800
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Cc: Bitcoin Development <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] Stealth Addresses
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On Sat, Jan 18, 2014 at 3:12 PM, Jeremy Spilman <jeremy@taplink.co> wrote:
> In the case where payment is being sent only to Q1, and Q2 is for discove=
ry only, perhaps we could use a 160-bit curve for d2/Q2 and e/P resulting i=
n 20 byte vs 32 bytes in the OP_RETURN, and of course faster multiplication=
.
>
> 80-bits of security I assume still greatly exceeds the actual level of pr=
ivacy you get with the overall solution, and since Q2 is never protecting a=
ctual funds...
>
> But if it's a "real weakening" of the privacy then definitely not worth i=
t, and even the added complexity of another curve seems possibly not worth =
it...
Well super-fast hand optimized code for (your choice of) 160 bit curve
may not ever exist, making it slower in practice. Plus the extra code
to carry around even if it does exist=E2=80=A6
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