From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sog-mx-4.v43.ch3.sourceforge.com ([172.29.43.194] helo=mx.sourceforge.net) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1XndDI-0004Rx-9G for bitcoin-development@lists.sourceforge.net; Mon, 10 Nov 2014 00:52:12 +0000 Received-SPF: pass (sog-mx-4.v43.ch3.sourceforge.com: domain of gmail.com designates 209.85.213.176 as permitted sender) client-ip=209.85.213.176; envelope-from=gmaxwell@gmail.com; helo=mail-ig0-f176.google.com; Received: from mail-ig0-f176.google.com ([209.85.213.176]) by sog-mx-4.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1XndDH-000118-9Q for bitcoin-development@lists.sourceforge.net; Mon, 10 Nov 2014 00:52:12 +0000 Received: by mail-ig0-f176.google.com with SMTP id l13so17039619iga.9 for ; Sun, 09 Nov 2014 16:52:06 -0800 (PST) MIME-Version: 1.0 X-Received: by 10.50.50.228 with SMTP id f4mr21191247igo.49.1415580725969; Sun, 09 Nov 2014 16:52:05 -0800 (PST) Received: by 10.107.168.211 with HTTP; Sun, 9 Nov 2014 16:52:05 -0800 (PST) In-Reply-To: References: Date: Mon, 10 Nov 2014 00:52:05 +0000 Message-ID: From: Gregory Maxwell To: Tier Nolan Content-Type: text/plain; charset=UTF-8 X-Spam-Score: -1.6 (-) 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 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (gmaxwell[at]gmail.com) -0.0 SPF_PASS SPF: sender matches SPF record -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature X-Headers-End: 1XndDH-000118-9Q Cc: Bitcoin Dev Subject: Re: [Bitcoin-development] BIP draft - Auxiliary Header Format 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, 10 Nov 2014 00:52:12 -0000 Some initial comments... Tying in the protocol changes is really confusing and the fact that they seem to be required out the gates would seemingly make this much harder to deploy. Is there a need to do that? Why can't the p2p part be entirely separate from the comitted data? On Mon, Nov 10, 2014 at 12:39 AM, Tier Nolan wrote: > I made some changes to the draft. The merkleblock now has the auxiliary > header information too. > > There is a tradeoff between overhead and delayed transactions. Is 12.5% > transactions being delayed to the next block unacceptable? Would adding > padding transactions be an improvement? > > Creating the "seed" transactions is an implementation headache. > > Each node needs to have control over an UTXO to create the final transaction > in the block that has the digest of the auxiliary header. This means that > it is not possible to simply start a node and have it mine. It has to > somehow be given the private key. If two nodes were given the same key by > accident, then one could end up blocking the other. > > On one end of the scale is adding a transaction with a few thousand outputs > into the block chain. The signatures for locktime restricted transactions > that spend those outputs could be hard-coded into the software. This is the > easiest to implement, but would mean a large table of signatures. The > person who generates the signature list would have to be trusted not to > spend the outputs early. > > The other end of the scale means that mining nodes need to include a wallets > to manage their UTXO entry. Miners can split a zero value output into lots > of outputs, if they wish. > > A middle ground would be for nodes to be able to detect the special > transactions and use them. A server could send out timelocked transactions > that pay to a particular address but the transaction would be timelocked. > The private key for the output would be known. However, miners who mine > version 2 blocks wouldn't be able to spend them early. > > > On Sat, Nov 8, 2014 at 11:45 PM, Tier Nolan wrote: >> >> I created a draft BIP detailing a way to add auxiliary headers to Bitcoin >> in a bandwidth efficient way. The overhead per auxiliary header is only >> around 104 bytes per header. This is much smaller than would be required by >> embedding the hash of the header in the coinbase of the block. >> >> It is a soft fork and it uses the last transaction in the block to store >> the hash of the auxiliary header. >> >> It makes use of the fact that the last transaction in the block has a much >> less complex Merkle branch than the other transactions. >> >> https://github.com/TierNolan/bips/blob/aux_header/bip-aux-header.mediawiki >> > > > ------------------------------------------------------------------------------ > > _______________________________________________ > Bitcoin-development mailing list > Bitcoin-development@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/bitcoin-development >