Received: from sog-mx-3.v43.ch3.sourceforge.com ([172.29.43.193] helo=mx.sourceforge.net) by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1SZ1LM-000380-Sw for bitcoin-development@lists.sourceforge.net; Mon, 28 May 2012 14:54:48 +0000 Received-SPF: pass (sog-mx-3.v43.ch3.sourceforge.com: domain of coinlab.com designates 209.85.214.175 as permitted sender) client-ip=209.85.214.175; envelope-from=peter@coinlab.com; helo=mail-ob0-f175.google.com; Received: from mail-ob0-f175.google.com ([209.85.214.175]) by sog-mx-3.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-MD5:128) (Exim 4.76) id 1SZ1LL-00061A-J5 for bitcoin-development@lists.sourceforge.net; Mon, 28 May 2012 14:54:48 +0000 Received: by obhx4 with SMTP id x4so543675obh.34 for ; Mon, 28 May 2012 07:54:42 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type:x-gm-message-state; bh=n1x59ASOHBIQCyWunexuFn41KOPJpr3Gwwe8f3b/Nuo=; b=R5oD3PaFE3PVm+H9zrqCDCvBgzk9BZIMkZ6bKQ0nPdY6bhpL4zWalP6r7OLoQfN2/0 fxtIjuafinUJSywbS79sJ9HfFystdZHidLI4823r3dL1gPyICPMGnrSOaKVoXwwDLpOy 00XutFCajAeM7KFHsJF3GzJK2leqyw9y1bzFpoX4kHlJ5Q8jdlKGNdlkydqZ+eLBwxQi d+HG+uYlTih4nzH6naciHB79YYtF3wvvEs/lxMjt6PrsIHF+f5WvAEvaqvXC+Im3bBle VQN1XcxmhKlEI2xHTG0EGZnnSTvAuaHlX/pkqhQrXJp1yjnKS2FF+cCLS6oDOvG/GVT9 b5BA== Received: by 10.182.139.2 with SMTP id qu2mr8175826obb.34.1338216881882; Mon, 28 May 2012 07:54:41 -0700 (PDT) MIME-Version: 1.0 Received: by 10.182.41.200 with HTTP; Mon, 28 May 2012 07:54:21 -0700 (PDT) In-Reply-To: <4FC0C401.1040600@justmoon.de> References: <4FC0C401.1040600@justmoon.de> From: Peter Vessenes Date: Mon, 28 May 2012 10:54:21 -0400 Message-ID: To: Stefan Thomas Content-Type: multipart/alternative; boundary=e89a8f838db1e0844c04c119e52e X-Gm-Message-State: ALoCoQkgUBM+aS6P1hEY9rkBhHycvc/YEhkaGCSrgDw97Mii6h9GOkurt2BoTDttnpQFfnT2/GYx X-Spam-Score: -0.5 (/) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. -1.5 SPF_CHECK_PASS SPF reports sender host as permitted sender for sender-domain -0.0 SPF_PASS SPF: sender matches SPF record 1.0 HTML_MESSAGE BODY: HTML included in message X-Headers-End: 1SZ1LL-00061A-J5 Cc: bitcoin-development@lists.sourceforge.net Subject: Re: [Bitcoin-development] Punishing empty blocks? X-BeenThere: bitcoin-development@lists.sourceforge.net X-Mailman-Version: 2.1.9 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 28 May 2012 14:54:49 -0000 --e89a8f838db1e0844c04c119e52e Content-Type: text/plain; charset=ISO-8859-1 One of the issues here though is that it would be nice if miners published their own tx rules -- it might be hard to impute them from data. I had started a thread about this on bitcoin.org some time ago, and I don't recall what the general outcome was. I had imagined an open service whereby a miner could publish a short string in their conbase tying to the service and the service would have different metadata, including the miner's transaction guarantees. We offered to host this before, and would still be willing to host such a service. Peter On Sat, May 26, 2012 at 7:52 AM, Stefan Thomas wrote: > Zooko is spot on - slower confirmations will give people a reason to set > higher fees. As soon as fees reach a level where they matter, even > botnet operators will be looking into ways of including transactions for > some extra profit. > > In the meantime slightly slower confirmations aren't a problem. Consider > that even if it takes four blocks to get your transaction included > instead of one, once it is included, you still benefit from every new > block in terms of security. So if you're looking for six confirmations > for example, even a three block delay will only be a 50% delay for you. > And of course there are techniques for instant transactions which > continue to be refined and improved. > > As for the proposed solutions: Punishing 1-tx blocks is complete and > utter nonsense. It's trivial to include a bogus second transaction. > > Any additional challenges towards miners like hashes of the previous > block are at best useless. If I was running a botnet, I'd just grab that > hash from a website (pretty good chance Blockchain.info will have it :P) > or mining pool or wherever and keep going undeterred. At worst they may > affect scalability one day. You might imagine a peer-to-peer network of > miners who for cost reasons don't download all blocks anymore, but > verify only a percentage of them at random. They might then exchange > messages about invalid blocks including a proof (invalid tx, merkle > branch) why the block is invalid. This is just one idea, the point is > that assumptions about what a legitimate miner looks like may not always > hold in the future. > > Finally, there is an ethical aspect as well. If a miner wishes not to > include my transaction that is his choice. He has no more an obligation > to sell his service to me than I have to buy it from him. If I really, > really want him to include my transaction I will have to offer to pay more. > > If we as developers think that confirmations are too slow or that more > blocks should include transactions, then the right measures would be: > > - Educating users about the relationship between confirmation speed and > fees > - Raising the default transaction fee > > Every market has a supply curve, so it is economically to be expected > that there will be some miners who don't include transactions, simply > because they are at that end of the supply curve where it is not worth > it for them to sell their service. All markets must have a certain > tension - there must be miners who don't include transactions for there > to be users who want their transactions included more quickly. In other > words there must be somebody not confirming if confirmations are to have > value. If you interfere with that all you'll accomplish is keep > transaction fees below market level, which will make the transition from > inflation-financed hashing to transaction-financed hashing more painful > and disruptive. > > Cheers, > > Stefan > > > ------------------------------------------------------------------------------ > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. Discussions > will include endpoint security, mobile security and the latest in malware > threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ > _______________________________________________ > Bitcoin-development mailing list > Bitcoin-development@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/bitcoin-development > -- Peter J. Vessenes CEO, CoinLab M: 206.595.9839 Skype: vessenes Google+ --e89a8f838db1e0844c04c119e52e Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable One of the issues here though is that it would be nice if miners published = their own tx rules -- it might be hard to impute them from data.

I had started a thread about this on bitcoin.org some time ago, and I don't recall what the general ou= tcome was.

I had imagined an open service whereby a miner could pu= blish a short string in their conbase tying to the service and the service = would have different metadata, including the miner's transaction guaran= tees.

We offered to host this before, and would still be will= ing to host such a service.

Peter

On Sat, May 26, 2012 at 7:52 AM, Stefan Thomas <moon@jus= tmoon.de> wrote:
Zooko is spot on - slower confirmations will= give people a reason to set
higher fees. As soon as fees reach a level where they matter, even
botnet operators will be looking into ways of including transactions for some extra profit.

In the meantime slightly slower confirmations aren't a problem. Conside= r
that even if it takes four blocks to get your transaction included
instead of one, once it is included, you still benefit from every new
block in terms of security. So if you're looking for six confirmations<= br> for example, even a three block delay will only be a 50% delay for you.
And of course there are techniques for instant transactions which
continue to be refined and improved.

As for the proposed solutions: Punishing 1-tx blocks is complete and
utter nonsense. It's trivial to include a bogus second transaction.

Any additional challenges towards miners like hashes of the previous
block are at best useless. If I was running a botnet, I'd just grab tha= t
hash from a website (pretty good chance Blockchain.info will have it :P) or mining pool or wherever and keep going undeterred. At worst they may
affect scalability one day. You might imagine a peer-to-peer network of
miners who for cost reasons don't download all blocks anymore, but
verify only a percentage of them at random. They might then exchange
messages about invalid blocks including a proof (invalid tx, merkle
branch) why the block is invalid. This is just one idea, the point is
that assumptions about what a legitimate miner looks like may not always hold in the future.

Finally, there is an ethical aspect as well. If a miner wishes not to
include my transaction that is his choice. He has no more an obligation
to sell his service to me than I have to buy it from him. If I really,
really want him to include my transaction I will have to offer to pay more.=

If we as developers think that confirmations are too slow or that more
blocks should include transactions, then the right measures would be:

- Educating users about the relationship between confirmation speed and fee= s
- Raising the default transaction fee

Every market has a supply curve, so it is economically to be expected
that there will be some miners who don't include transactions, simply because they are at that end of the supply curve where it is not worth
it for them to sell their service. All markets must have a certain
tension - there must be miners who don't include transactions for there=
to be users who want their transactions included more quickly. In other
words there must be somebody not confirming if confirmations are to have value. If you interfere with that all you'll accomplish is keep
transaction fees below market level, which will make the transition from inflation-financed hashing to transaction-financed hashing more painful
and disruptive.

Cheers,

Stefan

---------------------------------------------------------------------------= ---
Live Security Virtual Conference
Exclusive live event will cover all the ways today's security and
threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122= 263/
_______________________________________________
Bitcoin-development mailing list
Bitcoin-develo= pment@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/bitcoin-de= velopment



--
=
Peter J. Vessenes
CEO, CoinLab
M: 206.595.9839
Skype: vessenes
= Google+

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