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 18C419C for ; Sat, 1 Aug 2015 08:44:19 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.7.6 Received: from mail-lb0-f171.google.com (mail-lb0-f171.google.com [209.85.217.171]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 020608F for ; Sat, 1 Aug 2015 08:44:17 +0000 (UTC) Received: by lbqc9 with SMTP id c9so32406277lbq.1 for ; Sat, 01 Aug 2015 01:44:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type; bh=r2CgLAN0lkJ/BJSrEyk8R/MvTt/Ta/clOvdaU34EjL0=; b=v2FI4BndjvJDJ6nnZ8+U0uVyXOWZBzUFP6k0IcgHN3lAfO4t5GfTkbly0A8MfHTN6z gkHEd7kjeM8Q3TuBtx7bTUXDgOkdSihUqOKTbCdsHr7k5kz0EQgtk4R19mJJmfd9kOew qUy+2uuk3Q0BEBEE8KNzw2ypAdB1bPo9x3wrXkIRzTBW8x/pgLoQHvpAQYzXGtvQr+0g TbE7Xlb8ZHeGb7jyzbnS9OsvQ5k5n154yOAp/9S7khO92koG7Rwj9rInBApi5aR8ghSX QgZ0rDYc+XBd+ImUeYjjd0gUoE5+o10nbhWXc3dZhfrvJZHVheEcOCQW5v7F4cB+cOMX T/3A== X-Received: by 10.152.182.194 with SMTP id eg2mr7465337lac.71.1438418656260; Sat, 01 Aug 2015 01:44:16 -0700 (PDT) MIME-Version: 1.0 Received: by 10.25.21.94 with HTTP; Sat, 1 Aug 2015 01:43:56 -0700 (PDT) In-Reply-To: References: From: Hector Chu Date: Sat, 1 Aug 2015 09:43:56 +0100 Message-ID: To: Gregory Maxwell Content-Type: multipart/alternative; boundary=001a113491f20b79f5051c3bf1ae X-Spam-Status: No, score=-2.7 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,HTML_MESSAGE,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] Block size hard fork 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: Sat, 01 Aug 2015 08:44:19 -0000 --001a113491f20b79f5051c3bf1ae Content-Type: text/plain; charset=UTF-8 On 1 August 2015 at 01:17, Gregory Maxwell wrote: > One can quite easily transact in a way to intentionally produce such a > split to seperate the existance of your coins onto the seperate forks; > just as anyone would need to do to perform a reorg-and-respend attack > on a single blockchain. > Right. Why anyone would want to do this intentionally, however, is not clear. The coins would be worth less as they wouldn't be fungible across the chains anymore. Additionally, new coins will be issued, along with fees, on both > chains. These new outputs become spendable after 100 blocks, and any > transaction spending them can exist exclusively on one chain. > This is something that hadn't entered my mind when I made my assertions. At the moment I can't see any way to avoid this fact. Also any transaction whos casual history extends from one of the above > cases can exist only on one chain. This also means that someone who > has single-chain coins (via a conflict or from coinbase outputs) can > pay small amount to many users to get their wallets to consume them > and make more of the transactions single chain only-- if they wanted > the process to happen faster. > Wallets could detect this and notify the user. Due to Gresham's Law, I'll admit the observation that these outputs would likely get spent in preference (as they are less fungible), but whether the payee would be happy to accept them is a different matter. > Miners will migrate to the bigger chain in search of higher profits due > to higher volume of fees > > The migration remark is a considerable oversimplification. Imagine if > I released a version of the software programmed to reassign ownership > of a million of the earliest created unmoved coins to me at block > 400k, and then after that I made transaction to pay 5 coin/block in > fees. Would miners move to this chain? It pays more in fees! > Well in your example they wouldn't, because they know that your version wouldn't be accepted by the economic majority. But it's not as clear cut for the larger blocks case. They may move over gradually as they see the new chain gain acceptance, demonstrated by the higher trading volume on it. --001a113491f20b79f5051c3bf1ae Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
On 1= August 2015 at 01:17, Gregory Maxwell <gmaxwell@gmail.com>= wrote:
One can quite easily transact in = a way to intentionally produce such a
split to seperate the existance of your coins onto the seperate forks;
just as anyone would need to do to perform a reorg-and-respend attack
on a single blockchain.

Right. Why anyo= ne would want to do this intentionally, however, is not clear. The coins wo= uld be worth less as they wouldn't be fungible across the chains anymor= e.

Additionally, new coins will be issued, along with fees, on both
chains. These new outputs become spendable after 100 blocks, and any
transaction spending them can exist exclusively on one chain.

This is something that hadn't entered my mind wh= en I made my assertions. At the moment I can't see any way to avoid thi= s fact.

Also any transaction whos casual history extends from one of the above
cases can exist only on one chain. This also means that someone who
has single-chain coins (via a conflict or from coinbase outputs) can
pay small amount to many users to get their wallets to consume them
and make more of the transactions single chain only-- if they wanted
the process to happen faster.

Wallets c= ould detect this and notify the user. Due to Gresham's Law, I'll ad= mit the observation that these outputs would likely get spent in preference= (as they are less fungible), but whether the payee would be happy to accep= t them is a different matter.

> Miners will migrate to the bigger chain in search of higher profits du= e to higher volume of fees

The migration remark is a considerable oversimplification. Imagine i= f
I released a version of the software programmed to reassign ownership
of a million of the earliest created unmoved coins to me at block
400k, and then after that I made transaction to pay 5 coin/block in
fees. Would miners move to this chain?=C2=A0 It pays more in fees!

Well in your example they wouldn't, because= they know that your version wouldn't be accepted by the economic major= ity. But it's not as clear cut for the larger blocks case. They may mov= e over gradually as they see the new chain gain acceptance, demonstrated by= the higher trading volume on it.=C2=A0

--001a113491f20b79f5051c3bf1ae--