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| author | Adam Back <adam@cypherspace.org> | 2013-10-01 21:11:43 +0200 |
|---|---|---|
| committer | bitcoindev <bitcoindev@gnusha.org> | 2013-10-01 19:11:54 +0000 |
| commit | 790baed830dcdb6db2b425551f66c36d2cc650c9 (patch) | |
| tree | 4b0407ef0a660e9fd97eb6ebb5d6785e46b06246 | |
| parent | be1f0eb9aa2727f459f298fc557431ceb553cc0c (diff) | |
| download | pi-bitcoindev-790baed830dcdb6db2b425551f66c36d2cc650c9.tar.gz pi-bitcoindev-790baed830dcdb6db2b425551f66c36d2cc650c9.zip | |
Re: [Bitcoin-development] homomorphic coin value (validatable but encrypted) (Re: smart contracts -- possible use case? yes or no?)
| -rw-r--r-- | 74/3f3c10a72e7fc9e20bc598a0db4c7e5e08b601 | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/74/3f3c10a72e7fc9e20bc598a0db4c7e5e08b601 b/74/3f3c10a72e7fc9e20bc598a0db4c7e5e08b601 new file mode 100644 index 000000000..cd47c811d --- /dev/null +++ b/74/3f3c10a72e7fc9e20bc598a0db4c7e5e08b601 @@ -0,0 +1,132 @@ +Received: from sog-mx-2.v43.ch3.sourceforge.com ([172.29.43.192] + helo=mx.sourceforge.net) + by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) + (envelope-from <adam.back@gmail.com>) id 1VR5MQ-0007RL-7j + for bitcoin-development@lists.sourceforge.net; + Tue, 01 Oct 2013 19:11:54 +0000 +Received-SPF: pass (sog-mx-2.v43.ch3.sourceforge.com: domain of gmail.com + designates 74.125.83.46 as permitted sender) + client-ip=74.125.83.46; envelope-from=adam.back@gmail.com; + helo=mail-ee0-f46.google.com; +Received: from mail-ee0-f46.google.com ([74.125.83.46]) + by sog-mx-2.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) + (Exim 4.76) id 1VR5MO-0005VB-2L + for bitcoin-development@lists.sourceforge.net; + Tue, 01 Oct 2013 19:11:54 +0000 +Received: by mail-ee0-f46.google.com with SMTP id c13so3652342eek.33 + for <bitcoin-development@lists.sourceforge.net>; + Tue, 01 Oct 2013 12:11:45 -0700 (PDT) +X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; + d=1e100.net; s=20130820; + h=date:from:to:cc:subject:message-id:references:mime-version + :content-type:content-disposition:in-reply-to:user-agent; + bh=gEhIVy9w0Qsa6yHmhQOdSXBgkWGFLP8bUxJtqZPtPFk=; + b=DftSQEW8AqRJSpcUocHcG8oCN4Cdqhb2zrhfxm4D5NvB4Izo7i4kz5Ws4Ut9BIoLfR + z5dpeWGg40FI2sKk/pkVPKZ8ndw5vc9Tl3aYbr2lctYtbkU7WG9fAexFihOY3AOvbm7M + 2ke0njSX9md9hqz8CR+EphojRsb61d2rTxSpuv04xXd8rt2jOWQpY0xWWiIvBd4StVxQ + cu3FOzpr4Pdy2GybaTUi1QylYHp8oY2KTad0Ko/o/DFKoRW6B4Quz/JllU4t/qa7jRjz + OtyG9sXqKTZ7wh2RWduNw9uQMeJBA34kZ4wx886hs5H3DN3waPJ1xnoGSC93hh/flk0+ + 1OFQ== +X-Received: by 10.14.177.199 with SMTP id d47mr47846447eem.14.1380654705694; + Tue, 01 Oct 2013 12:11:45 -0700 (PDT) +Received: from netbook (c83-90.i07-21.onvol.net. 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[URIs: bitcointalk.org] +X-Headers-End: 1VR5MO-0005VB-2L +Cc: Bitcoin Dev <bitcoin-development@lists.sourceforge.net> +Subject: Re: [Bitcoin-development] homomorphic coin value (validatable but + encrypted) (Re: smart contracts -- possible use case? yes or no?) +X-BeenThere: bitcoin-development@lists.sourceforge.net +X-Mailman-Version: 2.1.9 +Precedence: list +List-Id: <bitcoin-development.lists.sourceforge.net> +List-Unsubscribe: <https://lists.sourceforge.net/lists/listinfo/bitcoin-development>, + <mailto:bitcoin-development-request@lists.sourceforge.net?subject=unsubscribe> +List-Archive: <http://sourceforge.net/mailarchive/forum.php?forum_name=bitcoin-development> +List-Post: <mailto:bitcoin-development@lists.sourceforge.net> +List-Help: <mailto:bitcoin-development-request@lists.sourceforge.net?subject=help> +List-Subscribe: <https://lists.sourceforge.net/lists/listinfo/bitcoin-development>, + <mailto:bitcoin-development-request@lists.sourceforge.net?subject=subscribe> +X-List-Received-Date: Tue, 01 Oct 2013 19:11:54 -0000 + +Err actually not (efficient) I made a mistake that came out when I started +writing it up about how the t parameter in the proof relates to bitcoin +precision and coin representation (I thought t=2, but t=51). Damn! Back to +the not so efficient version (which is more zerocoin-esque in size/cost), or +the more experimental Schoenmaker non-standard p, q non EC one, or other +creative ideas to change the coin representation to simplify the proof (of +which this was a failed attempt). See the bitcointalk thread for details. + +https://bitcointalk.org/index.php?topic=305791.new#new + +Adam + +On Tue, Oct 01, 2013 at 04:26:03PM +0200, Adam Back wrote: +>On Sun, Sep 29, 2013 at 10:49:00AM -0700, Mark Friedenbach wrote: +>>This kind of thing - providing external audits of customer accounts +>>without revealing private data - would be generally useful beyond +>>taxation. If you have any solutions, I'd be interested to hear them +>>(although bitcoin-dev is probably not the right place yet). +> +>Thanks for providing the impetus to write down the current state, the +>efficient version of which I only figured out a few days ago :) +> +>I have been researching this for a few months on and off, because it seems +>like an interesting construct in its own right, a different aspect of +>payment privacy (eg for auditable but commercial sensistive information) but +>also that other than its direct use it may enable some features that we have +>not thought of yet. +> +>I moved it to bitcointalk: +> +>https://bitcointalk.org/index.php?topic=305791.new#new +> +>Its efficient finally (after many dead ends): approximately 2x cost of +>current in terms of coin size and coin verification cost, however it also +>gives some perf advantages back in a different way - necessary changes to +>schnorr (EC version of Schnorr based proofs) allow n of n multiparty sigs, +>or k of n multiparty sigs for the verification cost and signature size of +>one pair of ECS signatures, for n > 2 its a space and efficiency improvement +>over current bitcoin. +> +>Adam + + |