Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 699424A2 for ; Thu, 23 Jul 2015 04:55:48 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from s47.web-hosting.com (s47.web-hosting.com [199.188.200.16]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 0AA34E9 for ; Thu, 23 Jul 2015 04:55:48 +0000 (UTC) Received: from localhost ([::1]:36105 helo=server47.web-hosting.com) by server47.web-hosting.com with esmtpsa (TLSv1:DHE-RSA-AES256-SHA:256) (Exim 4.82) (envelope-from ) id 1ZI8Xq-0026lL-Q0 for bitcoin-dev@lists.linuxfoundation.org; Thu, 23 Jul 2015 00:55:46 -0400 Received: from 119.246.245.241 ([119.246.245.241]) by server47.web-hosting.com (Horde Framework) with HTTP; Thu, 23 Jul 2015 04:55:46 +0000 Date: Thu, 23 Jul 2015 04:55:46 +0000 Message-ID: <20150723045546.Horde.KiM4VIQqwnFJ3lwdFrO-2w3@server47.web-hosting.com> From: jl2012@xbt.hk To: bitcoin-dev@lists.linuxfoundation.org References: In-Reply-To: User-Agent: Internet Messaging Program (IMP) H5 (6.1.4) Content-Type: text/plain; charset=UTF-8; format=flowed; DelSp=Yes MIME-Version: 1.0 Content-Disposition: inline X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - server47.web-hosting.com X-AntiAbuse: Original Domain - lists.linuxfoundation.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - xbt.hk X-Get-Message-Sender-Via: server47.web-hosting.com: authenticated_id: jl2012@xbt.hk X-Source: X-Source-Args: X-Source-Dir: X-From-Rewrite: unmodified, already matched X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00,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 Subject: Re: [bitcoin-dev] BIP: Short Term Use Addresses for Scalability 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: Thu, 23 Jul 2015 04:55:48 -0000 Quoting Gavin Andresen via bitcoin-dev : > On Wed, Jul 22, 2015 at 4:34 PM, Tier Nolan via bitcoin-dev < > bitcoin-dev@lists.linuxfoundation.org> wrote: > >> It also requires most clients to be updated to support the new address >> system. > > > That's the killer: introducing Yet Another Type of Bitcoin Address takes a > very long time and requires a lot of people to change their code. At least, > that was the lesson learned when we introduced P2SH addresses. > > I think it's just not worth it for a very modest space savings (10 bytes, > when scriptSig+scriptPubKey is about 120 bytes), especially with the > extreme decrease in security (going from 2^160 to 2^80 to brute-force). > > -- > -- > Gavin Andresen I think it would only save ~5% with all overhead (value, sequence, locktime, version, etc.) counted A better way is to introduce shorter ECDSA keys, which will save a lot of space for public key and signature. It is safe as long as the output value is much lower than the cost of attack. If this happens, I think it will be part of the OP_MAST which will require a new address type anyway.