Received: from sog-mx-2.v43.ch3.sourceforge.com ([172.29.43.192] helo=mx.sourceforge.net) by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1WYDDu-0003lS-G6 for bitcoin-development@lists.sourceforge.net; Thu, 10 Apr 2014 11:32:50 +0000 Received-SPF: pass (sog-mx-2.v43.ch3.sourceforge.com: domain of gmail.com designates 209.85.223.178 as permitted sender) client-ip=209.85.223.178; envelope-from=pieter.wuille@gmail.com; helo=mail-ie0-f178.google.com; Received: from mail-ie0-f178.google.com ([209.85.223.178]) by sog-mx-2.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1WYDDt-000368-KN for bitcoin-development@lists.sourceforge.net; Thu, 10 Apr 2014 11:32:50 +0000 Received: by mail-ie0-f178.google.com with SMTP id lx4so3625774iec.23 for ; Thu, 10 Apr 2014 04:32:44 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.42.120.15 with SMTP id d15mr12798467icr.35.1397129564317; Thu, 10 Apr 2014 04:32:44 -0700 (PDT) Received: by 10.50.141.135 with HTTP; Thu, 10 Apr 2014 04:32:44 -0700 (PDT) In-Reply-To: References: <534570A2.9090502@gmx.de> <0B038624-8861-438E-B7B1-566B4A8E126B@bitsofproof.com> Date: Thu, 10 Apr 2014 13:32:44 +0200 Message-ID: From: Pieter Wuille To: Wladimir Content-Type: text/plain; charset=ISO-8859-1 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 (pieter.wuille[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: 1WYDDt-000368-KN Cc: Bitcoin Dev Subject: Re: [Bitcoin-development] Bitcoind-in-background mode for SPV wallets 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: Thu, 10 Apr 2014 11:32:50 -0000 There were earlier discussions. The two ideas were either using one or a few service bits to indicate availability of blocks, or to extend addr messages with some flags to indicate this information. I wonder whether we can't have a hybrid: bits to indicate general degree of availability of blocks (none, only recent, everything), but indicate actual availability only upon actually connecting (through a "version" extension, or - preferably - a separate message). Reason is that the actual blocks available are likely to change frequently (if you keep the last week of blocks, a 3-day old addr entry will have quite outdated information), and not that important to actual peer selection - only to drive the decision which blocks to ask after connection. On Thu, Apr 10, 2014 at 1:09 PM, Wladimir wrote: > On Thu, Apr 10, 2014 at 8:04 AM, Tamas Blummer > wrote: >> >> Serving headers should be default but storing and serving full blocks >> configurable to ranges, so people can tailor to their bandwith and space >> available. > > > I do agree that it is important. > > This does require changes to the P2P protocol, as currently there is no way > for a node to signal that they store only part of the block chain. Also, > clients will have to be modified to take this into account. Right now they > are under the assumption that every full node can send them every (previous) > block. > > What would this involve? > > Do you know of any previous work towards this? > > Wladimir > > > ------------------------------------------------------------------------------ > Put Bad Developers to Shame > Dominate Development with Jenkins Continuous Integration > Continuously Automate Build, Test & Deployment > Start a new project now. Try Jenkins in the cloud. > http://p.sf.net/sfu/13600_Cloudbees > _______________________________________________ > Bitcoin-development mailing list > Bitcoin-development@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/bitcoin-development >