Received-SPF: pass (sog-mx-4.v43.ch3.sourceforge.com: domain of gmail.com
	designates 209.85.219.46 as permitted sender)
	client-ip=209.85.219.46; envelope-from=mh.in.england@gmail.com;
	helo=mail-oa0-f46.google.com; 
MIME-Version: 1.0
Sender: mh.in.england@gmail.com
In-Reply-To: <CAPg+sBgz2pLOkc3WL1sG3pJpdVqUZRwEfO9YaC-62vQyWLLW2Q@mail.gmail.com>
References: <CAPg+sBjSe23eADMxu-1mx0Kg2LGkN+BSNByq0PtZcMxAMh0uTg@mail.gmail.com>
	<CANEZrP3FA-5z3gAC1aYbG2EOKM2eDyv7zX3S9+ia2ZJ0LPkKiA@mail.gmail.com>
	<CAPg+sBjz8SbqU=2YXrXzwzmvz+NUbokD6KbPwZ5QAXSqCdi++g@mail.gmail.com>
	<CANEZrP2X9A0kBvN8=+G+dn_uqbSYfNhw7dm4od_yfJqDUoxHWg@mail.gmail.com>
	<CAPg+sBgz2pLOkc3WL1sG3pJpdVqUZRwEfO9YaC-62vQyWLLW2Q@mail.gmail.com>
Date: Fri, 3 May 2013 16:06:29 +0200
Message-ID: <CANEZrP2aaOyv4U12-moux--OhZQdK7rXC24YN61o6LQ0a+bK6g@mail.gmail.com>
From: Mike Hearn <mike@plan99.net>
To: Pieter Wuille <pieter.wuille@gmail.com>
Content-Type: multipart/alternative; boundary=001a11c249f689cce604dbd0db85
Cc: Bitcoin Dev <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] Service bits for pruned nodes
Precedence: list

--001a11c249f689cce604dbd0db85
Content-Type: text/plain; charset=UTF-8

> Yes, I like that better than broadcasting the exact height starting at
> which you serve (though I would put that information immediately in the
> version announcement). I don't think we can rely on the addr broadcasting
> mechanism for fast information exchange anyway. One more problem with this:
> DNS seeds cannot convey this information (neither do they currently convey
> service bits, but at least those can be indexed separately, and served
> explicitly through asking for a specific subdomain or so).
>

That's true, but we can extend the DNS seeding protocol a little bit - you
could query <current-chain-height>.dnsseed.whatever.com and the DNS server
then only returns nodes it knows matches your requirement.

This might complicate existing seeds a bit, and it's a bit of a hack, but
protocol-wise it's still possible. Of course if you want to add more
dimensions it gets uglier fast.

--001a11c249f689cce604dbd0db85
Content-Type: text/html; charset=UTF-8
Content-Transfer-Encoding: quoted-printable

<div dir=3D"ltr"><div class=3D"gmail_extra"><div class=3D"gmail_quote"><div=
>=C2=A0</div><blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;b=
order-left:1px #ccc solid;padding-left:1ex"><div dir=3D"ltr"><div class=3D"=
gmail_extra"><div class=3D"gmail_quote">
<div>Yes, I like that better than broadcasting the exact height starting at=
 which you serve (though I would put that information immediately in the ve=
rsion announcement). I don&#39;t think we can rely on the addr broadcasting=
 mechanism for fast information exchange anyway. One more problem with this=
: DNS seeds cannot convey this information (neither do they currently conve=
y service bits, but at least those can be indexed separately, and served ex=
plicitly through asking for a specific subdomain or so).</div>
</div></div></div></blockquote><div><br></div><div style>That&#39;s true, b=
ut we can extend the DNS seeding protocol a little bit - you could query &l=
t;current-chain-height&gt;.<a href=3D"http://dnsseed.whatever.com">dnsseed.=
whatever.com</a> and the DNS server then only returns nodes it knows matche=
s your requirement.</div>
<div style><br></div><div style>This might complicate existing seeds a bit,=
 and it&#39;s a bit of a hack, but protocol-wise it&#39;s still possible. O=
f course if you want to add more dimensions it gets uglier fast.</div><div>
=C2=A0<br></div></div></div></div>

--001a11c249f689cce604dbd0db85--