Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 9ED46C56 for ; Tue, 8 Dec 2015 21:41:09 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.7.6 Received: from mail-qg0-f51.google.com (mail-qg0-f51.google.com [209.85.192.51]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id C3A29116 for ; Tue, 8 Dec 2015 21:41:08 +0000 (UTC) Received: by qgec40 with SMTP id c40so38495364qge.2 for ; Tue, 08 Dec 2015 13:41:08 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=c8mAZM1uzKhiCVKY34jBGqWTaKPmJo4XOrdaDOUN0YU=; b=I3hl/QKu2bNKl53FdTwXNXM8zFeUUq+bJaMTP4jW6zXhY0mdWu3d9dgFz3jSiSDuZF nJMfK7ueKgjJRAc+N+CRjIJSPiGGXvsd/ftdYU2c0Uzxsfp70R+idYFNGPd9GCjPeyY4 Hzug8LKmR98w+cdrtyonjX40edxre4b+u6ahARttBpXsmJbDMvSRv3BgQwtaep5HsoCt FwOvsnsAfhSUKebr9mP57/fuuwLcBJDIgMGB/PwgHwjk9IZUnbUKETva3CjD1/x56+bZ fWyiNWGNT5kIBhra1Xewi3L12L++GJYQCc4VnD0YKXfYyUOi4o+8XyGZITELxHnjnanu tn/Q== MIME-Version: 1.0 X-Received: by 10.55.75.216 with SMTP id y207mr2611567qka.19.1449610867978; Tue, 08 Dec 2015 13:41:07 -0800 (PST) Received: by 10.140.101.112 with HTTP; Tue, 8 Dec 2015 13:41:07 -0800 (PST) In-Reply-To: <56674BA9.8090702@gmail.com> References: <56674280.3010003@gmail.com> <56674BA9.8090702@gmail.com> Date: Tue, 8 Dec 2015 16:41:07 -0500 Message-ID: From: Akiva Lichtner To: Patrick Strateman Content-Type: multipart/alternative; boundary=001a114a7e70d93762052669d4a0 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 X-Mailman-Approved-At: Wed, 09 Dec 2015 01:50:53 +0000 Cc: Bitcoin Dev Subject: Re: [bitcoin-dev] Scaling by Partitioning 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: Tue, 08 Dec 2015 21:41:09 -0000 --001a114a7e70d93762052669d4a0 Content-Type: text/plain; charset=UTF-8 If the system is modified to scale up that means the number of transactions is going up. That means the number of miners can also go up, and so will the portion of malicious nodes. At least this seems reasonable. The problem with partitions is that an attacker can focus on one partition. However because the number of miners also increases any attacks will fail as long as the miners are willing to work on any partition, which is easily accomplished by round-robin. Since there are N times more miners each miner still does the same amount of work. The system scales by partitioning the money supply and increasing the number of miners. On Tue, Dec 8, 2015 at 4:29 PM, Patrick Strateman via bitcoin-dev < bitcoin-dev@lists.linuxfoundation.org> wrote: > If partition is selected from a random key (the hash of the output for > example) then payment recipients would need to operate a full node on each > of the chains. > > What's the point of partitioning if virtually everybody needs to operate > each partition? > > The mining aspect has it's own set of issues, but I'm not going to get > into those. > > On 12/08/2015 01:23 PM, Akiva Lichtner wrote: > > It's true that miners would have to be prepared to work on any partition. > I don't see where the number affects defeating double spending, what > matters is the nonce in the block that keeps the next successful miner > random. > > I expect that the number of miners would be ten times larger as well, so > an attacker would have no advantage working on one partition. > > On Tue, Dec 8, 2015 at 3:50 PM, Patrick Strateman via bitcoin-dev < > > bitcoin-dev@lists.linuxfoundation.org> wrote: > >> Payment recipients would need to operate a daemon for each chain, thus >> guaranteeing no scaling advantage. >> >> (There are other issues, but I believe that to be enough of a show >> stopper not to continue). >> >> On 12/08/2015 08:27 AM, Akiva Lichtner via bitcoin-dev wrote: >> >> Hello, >> >> I am seeking some expert feedback on an idea for scaling Bitcoin. As a >> brief introduction: I work in the payment industry and I have twenty years' >> experience in development. I have some experience with process groups and >> ordering protocols too. I think I understand Satoshi's paper but I admit I >> have not read the source code. >> >> The idea is to run more than one simultaneous chain, each chain defeating >> double spending on only part of the coin. The coin would be partitioned by >> radix (or modulus, not sure what to call it.) For example in order to >> multiply throughput by a factor of ten you could run ten parallel chains, >> one would work on coin that ends in "0", one on coin that ends in "1", and >> so on up to "9". >> >> The number of chains could increase automatically over time based on the >> moving average of transaction volume. >> >> Blocks would have to contain the number of the partition they belong to, >> and miners would have to round-robin through partitions so that an attacker >> would not have an unfair advantage working on just one partition. >> >> I don't think there is much impact to miners, but clients would have to >> send more than one message in order to spend money. Client messages will >> need to enumerate coin using some sort of compression, to save space. This >> seems okay to me since often in computing client software does have to >> break things up in equal parts (e.g. memory pages, file system blocks,) and >> the client software could hide the details. >> >> Best wishes for continued success to the project. >> >> Regards, >> Akiva >> >> P.S. I found a funny anagram for SATOSHI NAKAMOTO: "NSA IS OOOK AT MATH" >> >> >> >> _______________________________________________ >> bitcoin-dev mailing listbitcoin-dev@lists.linuxfoundation.orghttps://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev >> >> >> >> _______________________________________________ >> bitcoin-dev mailing list >> bitcoin-dev@lists.linuxfoundation.org >> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev >> >> > > > _______________________________________________ > bitcoin-dev mailing list > bitcoin-dev@lists.linuxfoundation.org > https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev > > --001a114a7e70d93762052669d4a0 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
If the system is modified to scale up that means= the number of transactions is going up. That means the number of miners ca= n also go up, and so will the portion of malicious nodes. At least this see= ms reasonable. The problem with partitions is that an attacker can focus on= one partition. However because the number of miners also increases any att= acks will fail as long as the miners are willing to work on any partition, = which is easily accomplished by round-robin.

Since there are N= times more miners each miner still does the same amount of work. The syste= m scales by partitioning the money supply and increasing the number of mine= rs.



On Tue, Dec 8, 2015 at 4:29 PM, Patrick Str= ateman via bitcoin-dev <bitcoin-dev@lists.linuxfoundat= ion.org> wrote:
=20 =20 =20
If partition is selected from a random key (the hash of the output for example) then payment recipients would need to operate a full node on each of the chains.

What's the point of partitioning if virtually everybody needs to operate each partition?

The mining aspect has it's own set of issues, but I'm not going= to get into those.

On 12/08/2015 01:23 PM, Akiva Lichtner wrote:
It's true that miners would have to be prepared to work on any partition. I don't see where the number affects defeating double spending, what matters is the nonce in the block that keeps the next successful miner random.

I expect that the number of miners would be ten times larger as well, so an attacker would have no advantage working on one partition.

On Tue, Dec 8, 2015 at 3:50 PM, Patrick Strateman via bitcoin-dev <bitcoin-dev@l= ists.linuxfoundation.org> wrote:
Payment recipients would need to operate a daemon for each chain, thus guaranteeing no scaling advantage.

(There are other issues, but I believe that to be enough of a show stopper not to continue).

On 12/08/2015 08:27 AM, Akiva Lichtner via bitcoin-dev wrote:
Hello,

I am seeking some expert feedback on an idea for scaling Bitcoin. As a brief introduction: I work in the payment industry and I have twenty years' experience in development. I have some experience with process groups and ordering protocols too. I think I understand Satoshi's paper but I admit = I have not read the source code.

The idea is to run more than one simultaneous chain, each chain defeating double spending on only part of the coin. The coin would be partitioned by radix (or modulus, not sure what to call it.) For example in order to multiply throughput by a factor of ten you could run ten parallel chains, one would work on coin that ends in "0", one on coin that ends in &q= uot;1", and so on up to "9".

The number of chains could increase automatically over time based on the moving average of transaction volume.

Blocks would have to contain the number of the partition they belong to, and miners would have to round-robin through partitions so that an attacker would not have an unfair advantage working on just one partition.

I don't think there is much impact to miners, but clients would have to send more than one message in order to spend money. Client messages will need to enumerate coin using some sort of compression, to save space. This seems okay to me since often in computing client software does have to break things up in equal parts (e.g. memory pages, file system blocks,) and the client software could hide the details.

Best wishes for continued success to the project.

Regards,
Akiva

P.S. I found a funny anagram for SATOSHI NAKAMOTO: "NSA IS OOOK AT MATH"



_______________________________________________
bitcoin-dev mailing list
=
bitcoin-dev@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/bitcoi=
n-dev


_______________________________________________
bitcoin-dev mailing list
bitcoin-dev@lists.linuxfoundation.org
https://lists.linuxfoundat= ion.org/mailman/listinfo/bitcoin-dev




_______________________________________________
bitcoin-dev mailing list
bitcoin-dev@lists.= linuxfoundation.org
https://lists.linuxfoundation.org/mail= man/listinfo/bitcoin-dev


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