From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sog-mx-3.v43.ch3.sourceforge.com ([172.29.43.193] helo=mx.sourceforge.net) by sfs-ml-2.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1Yx6qe-00052b-K8 for bitcoin-development@lists.sourceforge.net; Tue, 26 May 2015 04:52:16 +0000 X-ACL-Warn: Received: from resqmta-po-06v.sys.comcast.net ([96.114.154.165]) by sog-mx-3.v43.ch3.sourceforge.com with esmtps (TLSv1:AES128-SHA:128) (Exim 4.76) id 1Yx6qd-0005Ye-9o for bitcoin-development@lists.sourceforge.net; Tue, 26 May 2015 04:52:16 +0000 Received: from resomta-po-07v.sys.comcast.net ([96.114.154.231]) by resqmta-po-06v.sys.comcast.net with comcast id YUs91q0044zp9eg01Us9Vv; Tue, 26 May 2015 04:52:09 +0000 Received: from crushinator.localnet ([IPv6:2601:6:4800:47f:1e4e:1f4d:332c:3bf6]) by resomta-po-07v.sys.comcast.net with comcast id YUs81q00A2JF60R01Us8Sd; Tue, 26 May 2015 04:52:09 +0000 From: Matt Whitlock To: Jim Phillips Date: Tue, 26 May 2015 00:52:07 -0400 Message-ID: <23111107.dfGN69SrR9@crushinator> User-Agent: KMail/4.14.8 (Linux/3.18.11-gentoo; KDE/4.14.8; x86_64; ; ) In-Reply-To: References: <2916218.tfdjj1Sv9m@crushinator> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Spam-Score: 0.0 (/) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [96.114.154.165 listed in list.dnswl.org] 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: 1Yx6qd-0005Ye-9o Cc: Bitcoin Dev Subject: Re: [Bitcoin-development] Zero-Conf for Full Node Discovery 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: Tue, 26 May 2015 04:52:16 -0000 On Monday, 25 May 2015, at 11:48 pm, Jim Phillips wrote: > Do any wallets actually do this yet? Not that I know of, but they do seed their address database via DNS, which you can poison if you control the LAN's DNS resolver. I did this for a Bitcoin-only Wi-Fi network I operated at a remote festival. We had well over a hundred lightweight wallets, all trying to connect to the Bitcoin P2P network over a very bandwidth-constrained Internet link, so I poisoned the DNS and rejected all outbound connection attempts on port 8333, to force all the wallets to connect to a single local full node, which had connectivity to a single remote node over the Internet. Thus, all the lightweight wallets at the festival had Bitcoin network connectivity, but we only needed to backhaul the Bitcoin network's transaction traffic once. > On May 25, 2015 11:37 PM, "Matt Whitlock" wrote: > > > This is very simple to do. Just ping the "all nodes" address (ff02::1) and > > try connecting to TCP port 8333 of each node that responds. Shouldn't take > > but more than a few milliseconds on any but the most densely populated LANs. > > > > > > On Monday, 25 May 2015, at 11:06 pm, Jim Phillips wrote: > > > Is there any work being done on using some kind of zero-conf service > > > discovery protocol so that lightweight clients can find a full node on > > the > > > same LAN to peer with rather than having to tie up WAN bandwidth? > > > > > > I envision a future where lightweight devices within a home use SPV over > > > WiFi to connect with a home server which in turn relays the transactions > > > they create out to the larger and faster relays on the Internet. > > > > > > In a situation where there are hundreds or thousands of small SPV devices > > > in a single home (if 21, Inc. is successful) monitoring the blockchain, > > > this could result in lower traffic across the slow WAN connection. And > > > yes, I realize it could potentially take a LOT of these devices before > > the > > > total bandwidth is greater than downloading a full copy of the > > blockchain, > > > but there's other reasons to host your own full node -- trust being one. > > > > > > -- > > > *James G. Phillips IV* > > > > > > > > > > > > *"Don't bunt. Aim out of the ball park. Aim for the company of > > immortals." > > > -- David Ogilvy* > > > > > > *This message was created with 100% recycled electrons. Please think > > twice > > > before printing.* > >