Received: from sog-mx-1.v43.ch3.sourceforge.com ([172.29.43.191] helo=mx.sourceforge.net) by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1Yx7AG-0001Bq-JR for bitcoin-development@lists.sourceforge.net; Tue, 26 May 2015 05:12:32 +0000 Received-SPF: pass (sog-mx-1.v43.ch3.sourceforge.com: domain of gmail.com designates 209.85.212.180 as permitted sender) client-ip=209.85.212.180; envelope-from=kgreenek@gmail.com; helo=mail-wi0-f180.google.com; Received: from mail-wi0-f180.google.com ([209.85.212.180]) by sog-mx-1.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1Yx7AF-0004f4-4k for bitcoin-development@lists.sourceforge.net; Tue, 26 May 2015 05:12:32 +0000 Received: by wicmx19 with SMTP id mx19so64125051wic.0 for ; Mon, 25 May 2015 22:12:25 -0700 (PDT) X-Received: by 10.194.179.2 with SMTP id dc2mr46220944wjc.120.1432617145113; Mon, 25 May 2015 22:12:25 -0700 (PDT) MIME-Version: 1.0 Received: by 10.27.20.1 with HTTP; Mon, 25 May 2015 22:12:04 -0700 (PDT) In-Reply-To: <2508972.mm4E72Fj6S@crushinator> References: <2916218.tfdjj1Sv9m@crushinator> <2508972.mm4E72Fj6S@crushinator> From: Kevin Greene Date: Mon, 25 May 2015 22:12:04 -0700 Message-ID: To: Matt Whitlock Content-Type: multipart/alternative; boundary=089e013d1954089fe40516f52c07 X-Spam-Score: -0.6 (/) 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 (kgreenek[at]gmail.com) -0.0 SPF_PASS SPF: sender matches SPF record 1.0 HTML_MESSAGE BODY: HTML included in message -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: 1Yx7AF-0004f4-4k 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 05:12:32 -0000 --089e013d1954089fe40516f52c07 Content-Type: text/plain; charset=UTF-8 This is true, but the device doesn't know if the LAN it's on is a safe network or a hotel wifi, for example. So there would be a tricky UX there. You'd have to ask the user during set up if this is a trusted LAN or not; or something like that. That may not be an issue though depending on the nature of the product. For example, Chromecast doesn't need any security protections against trolls on the same LAN. I guess it just depends on what you're planning to build. On Mon, May 25, 2015 at 9:56 PM, Matt Whitlock wrote: > Who would be performing a Sybil attack against themselves? We're talking > about a LAN here. All the nodes would be under the control of the same > entity. In that case, you actually want them all connecting solely to a > central hub node on the LAN, and the hub node should connect to "diverse > and unpredictable" other nodes on the Bitcoin network. > > > On Monday, 25 May 2015, at 9:46 pm, Kevin Greene wrote: > > This is something you actually don't want. In order to make it as > difficult > > as possible for an attacker to perform a sybil attack, you want to > choose a > > set of peers that is as diverse, and unpredictable as possible. > > > > > > On Mon, May 25, 2015 at 9:37 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.* > > > > > > > > > > ------------------------------------------------------------------------------ > > > One dashboard for servers and applications across > Physical-Virtual-Cloud > > > Widest out-of-the-box monitoring support with 50+ applications > > > Performance metrics, stats and reports that give you Actionable > Insights > > > Deep dive visibility with transaction tracing using APM Insight. > > > http://ad.doubleclick.net/ddm/clk/290420510;117567292;y > > > _______________________________________________ > > > Bitcoin-development mailing list > > > Bitcoin-development@lists.sourceforge.net > > > https://lists.sourceforge.net/lists/listinfo/bitcoin-development > > > > --089e013d1954089fe40516f52c07 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
This = is true, but the device doesn't know if the LAN it's on is a safe n= etwork or a hotel wifi, for example. So there would be a tricky UX there. Y= ou'd have to ask the user during set up if this is a trusted LAN or not= ; or something like that. That may not be an issue though depending on the = nature of the product. For example, Chromecast doesn't need any securit= y protections against trolls on the same LAN. I guess it just depends on wh= at you're planning to build.

On Mon, May 25, 2015 at 9:56 PM, Matt Whitlock <b= ip@mattwhitlock.name> wrote:
bip@mattwhitlock.name>
> wrote:
>
> > This is very simple to do. Just ping the "all nodes" ad= dress (ff02::1) and
> > try connecting to TCP port 8333 of each node that responds. Shoul= dn't take
> > but more than a few milliseconds on any but the most densely popu= lated 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 fu= ll node on
> > the
> > > same LAN to peer with rather than having to tie up WAN bandw= idth?
> > >
> > > 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 Inter= net.
> > >
> > > In a situation where there are hundreds or thousands of smal= l SPV devices
> > > in a single home (if 21, Inc. is successful) monitoring the = blockchain,
> > > this could result in lower traffic across the slow WAN conne= ction.=C2=A0 And
> > > yes, I realize it could potentially take a LOT of these devi= ces before
> > the
> > > total bandwidth is greater than downloading a full copy of t= he
> > blockchain,
> > > but there's other reasons to host your own full node -- = trust being one.
> > >
> > > --
> > > *James G. Phillips IV*
> > > <https://plus.google.com/u/0/11310703950129262= 5391/posts>
> > > <http://www.linkedin.com/in/ergophobe>
> > >
> > > *"Don't bunt. Aim out of the ball park. Aim for the= company of
> > immortals."
> > > -- David Ogilvy*
> > >
> > >=C2=A0 *This message was created with 100% recycled electrons= . Please think
> > twice
> > > before printing.*
> >
> >
> > -----------------------------------------------------------------= -------------
> > One dashboard for servers and applications across Physical-Virtua= l-Cloud
> > Widest out-of-the-box monitoring support with 50+ applications > > Performance metrics, stats and reports that give you Actionable I= nsights
> > Deep dive visibility with transaction tracing using APM Insight.<= br> > > http://ad.doubleclick.net/ddm/clk/290420510;117567292;= y
> > _______________________________________________
> > Bitcoin-development mailing list
> > Bitcoin-development@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/= bitcoin-development
> >

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