From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 1FF23F4D for ; Sun, 11 Mar 2018 12:44:52 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.7.6 Received: from mail-wr0-f181.google.com (mail-wr0-f181.google.com [209.85.128.181]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id E4C31360 for ; Sun, 11 Mar 2018 12:44:50 +0000 (UTC) Received: by mail-wr0-f181.google.com with SMTP id d10so569455wrf.3 for ; Sun, 11 Mar 2018 05:44:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:content-transfer-encoding:mime-version:subject:message-id:date :to; bh=kfiHsPIZP1QIUHROPcKtR6ev4xVMBdioM0vcbZK+OlM=; b=Atz6D94Orn5xaTzb1hEOVbxxKhLNY7Rvg3PBqa3tm7j4pN/zPRdX3ZGzcczJWXIbJN YVHkWNEdu7f5wpGFCUD9QEOi+/DUAkIxbw+r+L478e4zDfal01zDSNrZfbejR18PJwM6 xvRWbHVam2UXyHSGMmQ2mRooKkIyjCnzJR67Vwm8l/IM1pdf5K0//6S43aan0YDAATMY 82OEHlDCjI+Y+nn+DDpDppFM7qglhBlB3a80CoR9d5T1H3RLPJFfDQYr8lmhP4UtOqW/ XXC5wvlnFBNo9Bgq7QhvP1qa10lwPsOt4OAB6PgGfpXWo8H35TYHPXqhLfWmWFAJmDMX zIFQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:content-transfer-encoding:mime-version :subject:message-id:date:to; bh=kfiHsPIZP1QIUHROPcKtR6ev4xVMBdioM0vcbZK+OlM=; b=R03sssZTInIRLqs5iItylUUweYSqGzAm2iMY+pqFfy+QD2DraZFJDtFi1zrEPAdLrF ynoxSci1fVKuG4TSq3/DNvypJHgdPzZXfWF7vKh1wNCMMZpI92qGBNkSWHPcUROSTuIh aRu6tBiEiJkHpBrlWMC1jgRG1xyxVUvJHlhWchBvINLWT2Q+C+UlgxDsAmyYlioKUTsW YDZyzkIwLMBbKKfsUWmDsAdsQtObRw45BhBt7nHRX1FZjhadL8YuO9TOLgk1UfXkbk5X InlDD7OTAIqEYxWB9nIgEs7T/wjVtgvGKIbQbEsZ9wOK6m/HL9vUyn9q8LKnMJAh2wu9 gsuQ== X-Gm-Message-State: AElRT7Ho5iGodZXHhAC8wSKAGCnYWMhrojbjt09VJMIruuy4yVl3s1Ac NA1t4Z4TlywBYorCNqmNCa8JvQxx X-Google-Smtp-Source: AG47ELtOBEBgA3mV5UEMcb4EuuoKqkwUxB+fDkwWLbUbADzFacmF45IQmmb/gcCmXnE9yoWoE84f4w== X-Received: by 10.223.175.230 with SMTP id y38mr3667662wrd.26.1520772289245; Sun, 11 Mar 2018 05:44:49 -0700 (PDT) Received: from [192.168.1.32] ([178.60.38.49]) by smtp.gmail.com with ESMTPSA id k18sm3815775wmd.4.2018.03.11.05.44.48 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 11 Mar 2018 05:44:48 -0700 (PDT) From: =?utf-8?Q?JOSE_FEMENIAS_CA=C3=91UELO?= Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Mime-Version: 1.0 (Mac OS X Mail 10.2 \(3259\)) Message-Id: <90096274-9576-4A08-A86A-E1C4F3E3B5DE@gmail.com> Date: Sun, 11 Mar 2018 13:44:47 +0100 To: bitcoin-dev@lists.linuxfoundation.org X-Mailer: Apple Mail (2.3259) X-Spam-Status: No, score=-2.0 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org X-Mailman-Approved-At: Sun, 11 Mar 2018 13:58:08 +0000 Subject: [bitcoin-dev] Bulletproof CT as basis for election voting? X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Protocol Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 11 Mar 2018 12:44:52 -0000 If I understand Bulletproof Confidential Transactions properly, their = main virtue is being able to hide not the senders/receivers of a coin = but the amount transferred. That sounds to me like a perfect use case for an election. For instance, in my country, every citizen is issued a National ID Card = with a digital certificate.=20 So, a naive implementation could simply be that the Voting Authority, = sends a coin (1 coin =3D 1 vote) to each citizen above 18. This would be = an open transaction, so it is easily auditable. Later on, each voter sends her coin to her preferred party, as part of a = Bulletproof CT, along with 0 coins to other parties to disguise her = vote. In the end, each party will accrue as may votes as coins received. Is there any gotcha I=E2=80=99m missing here? Are there any missing = features required in Bulletproof to support this use case?=