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 EC972E57 for ; Sun, 1 Apr 2018 14:37:17 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.7.6 Received: from APC01-SG2-obe.outbound.protection.outlook.com (mail-oln040092253031.outbound.protection.outlook.com [40.92.253.31]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id AC195628 for ; Sun, 1 Apr 2018 14:37:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=live.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version; bh=noXDIEONnEWttm9EFiXWYHwxOAEggV+xEJ7jtMjSwtw=; b=J6HQCOZfTtJ9RW3rKHAGoIKs159kasGEoMEuyUh78MN44qQJKQ6fK5vvh+x/UX9LRVBATmfM/xPplJyoTC2Qeh+71IxOqqFMJkIypevWPXh01sAjWQ6a2H7cP5+cQLmRM/VtozKlP3B0q/V9dpr93CUTUfYIRLuz7I09i1XwhIVfzrdTBUdJ1/kajm8L6mZzEKtTcJMeS202o6TMRFj0YMbN6i/Ga0UfBQxAPG/aLjH+Ci0X4V5UbXn7mxmxeJplmRH0GI4M9hFGPNWSSi4LWzAtBrJj8BFhbghhk6CRlnkZgMr1840zBF0fD77VxttorZfcKqas6tuA/1VndglsdA== Received: from SG2APC01FT008.eop-APC01.prod.protection.outlook.com (10.152.250.58) by SG2APC01HT111.eop-APC01.prod.protection.outlook.com (10.152.251.189) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.20.631.7; Sun, 1 Apr 2018 14:37:13 +0000 Received: from PS2P216MB0179.KORP216.PROD.OUTLOOK.COM (10.152.250.60) by SG2APC01FT008.mail.protection.outlook.com (10.152.250.99) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.20.631.7 via Frontend Transport; Sun, 1 Apr 2018 14:37:13 +0000 Received: from PS2P216MB0179.KORP216.PROD.OUTLOOK.COM ([10.171.225.19]) by PS2P216MB0179.KORP216.PROD.OUTLOOK.COM ([10.171.225.19]) with mapi id 15.20.0631.013; Sun, 1 Apr 2018 14:37:13 +0000 From: Damian Williamson To: Eric Voskuil , Evan Klitzke , "Bitcoin Protocol Discussion" Thread-Topic: [bitcoin-dev] feature: Enhance privacy by change obfuscation Thread-Index: AQHTvlhNAdeVyrmKfEykHDGYNxE3lqPVfV8AgADcawCAFbbAYw== Date: Sun, 1 Apr 2018 14:37:13 +0000 Message-ID: References: <874lleexud.fsf@eklitzke.org>, In-Reply-To: Accept-Language: en-AU, en-US Content-Language: en-AU X-MS-Has-Attach: X-MS-TNEF-Correlator: x-incomingtopheadermarker: OriginalChecksum:E998A18893ABC8E705142B0B7B4E2CA0872889DB0DF528BB442DF759280D8499; UpperCasedChecksum:1C09BE9E2BC8D421985ACE2A9C9B7476ADB86486ACE2934CA95442A9364D5239; SizeAsReceived:7260; Count:46 x-ms-exchange-messagesentrepresentingtype: 1 x-tmn: [zg657aSB3yj92Wv1yABGUZPu5okfDbZg] x-ms-publictraffictype: Email x-microsoft-exchange-diagnostics: 1; SG2APC01HT111; 7:vIzvUH68Shp0E0Q//WJ0PNc2YIxhdprBVjl06ONtbZEiY7cdPhNUCxmlNJbgI8qIDWgfa17ERhmxEFT2vK4PNAoMp4HOTSqokDB05cpbKRHLqJR0BbkK7QmOpcRHQsGU/xUSIrC5QBWnPaT7yqVju99GlBorIzQVgHau8HLtru+Tb3rv3eAWpKDFfdenydWmaGVGBxKu/KHKBrFlA5opv5KGKxbQDDOg42CTzPWWcBU9huXYau5w5EOsnAlOawD6 x-incomingheadercount: 46 x-eopattributedmessage: 0 x-microsoft-antispam: UriScan:; BCL:0; PCL:0; RULEID:(7020095)(201702061078)(5061506573)(5061507331)(1603103135)(2017031320274)(2017031324274)(2017031323274)(2017031322404)(1601125374)(1603101448)(1701031045); SRVR:SG2APC01HT111; x-ms-traffictypediagnostic: SG2APC01HT111: x-ms-office365-filtering-correlation-id: f48dddbb-3fcc-435e-3e59-08d597de0f32 x-exchange-antispam-report-cfa-test: BCL:0; PCL:0; RULEID:(444000031); SRVR:SG2APC01HT111; BCL:0; PCL:0; RULEID:; SRVR:SG2APC01HT111; x-forefront-prvs: 06290ECA9D x-forefront-antispam-report: SFV:NSPM; SFS:(7070007)(98901004); DIR:OUT; SFP:1901; SCL:1; SRVR:SG2APC01HT111; H:PS2P216MB0179.KORP216.PROD.OUTLOOK.COM; FPR:; SPF:None; LANG:; x-microsoft-antispam-message-info: xReaYddQ7wn13/AWKwawYlqA6tPfwVhort4NWeQqg0H1wLjQwy0mBISu9mFxmE86PS4hD5x8XQWQsGKf9tAbIduDCwI7aBDWTMw3NsJmt8G99CObDVxlPeLEG5KVQkTMnuzl8HRlVgVP7jLMgugLdjiSrJ20HPzTworpKZW1B8HVUYwIcb2NPaN11Jk3zmRN spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM Content-Type: multipart/alternative; boundary="_000_PS2P216MB0179F3FE8D11A9161F0F502E9DA70PS2P216MB0179KORP_" MIME-Version: 1.0 X-OriginatorOrg: outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: f48dddbb-3fcc-435e-3e59-08d597de0f32 X-MS-Exchange-CrossTenant-originalarrivaltime: 01 Apr 2018 14:37:13.3621 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Internet X-MS-Exchange-CrossTenant-id: 84df9e7f-e9f6-40af-b435-aaaaaaaaaaaa X-MS-Exchange-Transport-CrossTenantHeadersStamped: SG2APC01HT111 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, HTML_MESSAGE, 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, 01 Apr 2018 14:50:38 +0000 Subject: Re: [bitcoin-dev] feature: Enhance privacy by change obfuscation 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, 01 Apr 2018 14:37:18 -0000 --_000_PS2P216MB0179F3FE8D11A9161F0F502E9DA70PS2P216MB0179KORP_ Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable I note that Electrum v3.0.6 has an option to use multiple change addresses.= It is off by default. Regards, Damian Williamson ________________________________ From: Eric Voskuil Sent: Monday, 19 March 2018 5:59:28 AM To: Evan Klitzke; Bitcoin Protocol Discussion Cc: Damian Williamson Subject: Re: [bitcoin-dev] feature: Enhance privacy by change obfuscation > This would be really expensive for the network due to the bloat in UTXO s= ize, a cost everyone has to pay for. Without commenting on the merits of this proposal, I=92d just like to corre= ct this common misperception. There is no necessary additional cost to the = network from the count of unspent outputs. This perception arises from an i= mplementation detail of particular node software. There is no requirement f= or redundant indexing of unspent outputs. e --_000_PS2P216MB0179F3FE8D11A9161F0F502E9DA70PS2P216MB0179KORP_ Content-Type: text/html; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable

I note that Electrum v3.0.6 has a= n option to use multiple change addresses. It is off by default.


Regards,

Damian Williamson

From: Eric Voskuil <eric= @voskuil.org>
Sent: Monday, 19 March 2018 5:59:28 AM
To: Evan Klitzke; Bitcoin Protocol Discussion
Cc: Damian Williamson
Subject: Re: [bitcoin-dev] feature: Enhance privacy by change obfusc= ation
 
> This would be really expensive for the networ= k due to the bloat in UTXO size, a cost everyone has to pay for.

Without commenting on the merits of this proposal, I=92d just like to corre= ct this common misperception. There is no necessary additional cost to the = network from the count of unspent outputs. This perception arises from an i= mplementation detail of particular node software. There is no requirement for redundant indexing of unspent o= utputs.

e
--_000_PS2P216MB0179F3FE8D11A9161F0F502E9DA70PS2P216MB0179KORP_--