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 983C9D56 for ; Sun, 13 Dec 2015 02:07:37 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.7.6 Received: from mail-io0-f181.google.com (mail-io0-f181.google.com [209.85.223.181]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 3B550133 for ; Sun, 13 Dec 2015 02:07:37 +0000 (UTC) Received: by ioae126 with SMTP id e126so13485977ioa.1 for ; Sat, 12 Dec 2015 18:07:36 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date:message-id:subject :from:to:cc:content-type; bh=/qcbeU8YFs9R2hnBHzkV6Ok+V2s51yIOPll9pSzs4Qo=; b=Qlgj9jNYN2S3Kd0a9d4NLrZiFgbEgaVOpPO+EhAdpAFZNiKMdcbQWbl8TZq3vggnDn Rg2Om4YOpwuVNGS30+96Gy+lApnpznSpj8zBi0Xyc+flE2gqQAtvlnUzpZadx5SsBOYI C6TMOMbiDP0jH99y9nQmfp61hbFq4NqB2Z2nJr8JPGe0DENDwBptwv3WIuJz+5SSDlO1 wOjRi17TwhEArt9qJ/4FtaJe6S8pzOiPhm5+WqSgZLG5HM46k5IxQFXtTVGj4DWwjin5 Wwm3/Blle8RVkHR67C3UfqYALKDXfb9f4h3vxHDex3JTVKgyrdQmPv/NOBwp/Nx/VySM 70gA== MIME-Version: 1.0 X-Received: by 10.107.34.199 with SMTP id i190mr24506717ioi.150.1449972456801; Sat, 12 Dec 2015 18:07:36 -0800 (PST) Sender: gmaxwell@gmail.com Received: by 10.107.192.70 with HTTP; Sat, 12 Dec 2015 18:07:36 -0800 (PST) In-Reply-To: References: <50e629572d8de852eb789d50b34da308@xbt.hk> <1449961269.2210.5.camel@yahoo.com> Date: Sun, 13 Dec 2015 02:07:36 +0000 X-Google-Sender-Auth: OqBKDTbqoMlNHvdjLBlv2_lc4Xs Message-ID: From: Gregory Maxwell To: Vincent Truong Content-Type: text/plain; charset=UTF-8 X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, FREEMAIL_FROM, RCVD_IN_DNSWL_LOW autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org Cc: Bitcoin Dev Subject: Re: [bitcoin-dev] Forget dormant UTXOs without confiscating bitcoin X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Development Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 13 Dec 2015 02:07:37 -0000 On Sun, Dec 13, 2015 at 1:00 AM, Vincent Truong via bitcoin-dev wrote: > have run a node/kept their utxo before they were aware of this change and > then realise miners have discarded their utxo. Oops? I believe you have misunderstood jl2012's post. His post does not cause the outputs to become discarded. They are still spendable, but the transactions must carry a membership proof to spend them. They don't have to have stored the data themselves, but they must get it from somewhere-- including archive nodes that serve this purpose rather than having every full node carry all that data forever. Please be conservative with the send button. The list loses its utility if every moderately complex idea is hit with reflexive opposition by people who don't understand it. Peter Todd has proposed something fairly similar with "STXO commitments". The primary argument against this kind of approach that I'm aware of is that the membership proofs get pretty big, and if too aggressive this trades bandwidth for storage, and storage is usually the cheaper resource. Though at least the membership proofs could be omitted when transmitting to a node which has signaled that it has kept the historical data anyways.