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From: Pieter Wuille <pieter.wuille@gmail.com>
Date: Wed, 8 Mar 2017 17:55:32 -0800
Message-ID: <CAPg+sBg-ihLOi4eq6mCti=bGtbe0sWYv3ScmWoEZ8d=dHDQ5Mw@mail.gmail.com>
To: Eric Voskuil <eric@voskuil.org>
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Cc: Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>,
	Libbitcoin Development <libbitcoin@lists.dyne.org>
Subject: Re: [bitcoin-dev] Unique node identifiers
Precedence: list

On Wed, Mar 8, 2017 at 5:16 PM, Eric Voskuil <eric@voskuil.org> wrote:
> On 03/08/2017 03:12 PM, Pieter Wuille wrote:
>> In that way, I see BIP150 as an extension of IP addresses, except more
>> secure against network-level attackers. If you believe the concept of
>> people establishing links along existing trust lines is a problem, you
>> should be arguing against features in Bitcoin software that allows
>> configuring preferred IP addresses to connect to as well (-addnode and
>> -connect in Bitcoin Core, for example).
>
> Weak identity is insufficient to produce the problem scenario that is at
> the heart of my concern (excluding people). It is this "[same] except
> more secure" distinction that is the problem. You brush past that as if
> it did not exist.

So you're saying that a -onlyacceptconnectionsfrom=IP option wouldn't
be a concern to you because it can't exclude people? Of course it can
exclude people - just not your ISP or a state-level attacker.

Please, Eric. I think I understand your concern, but this argument
isn't constructive either.

The proposal here is to introduce visible node identities on the
network. I think that's misguided as node count is irrelevant and
trivial to fake anyway. But you bringing up BIP150 here isn't useful
either. I know that you equate the concept of having verifiable
identity keys in the P2P with a step towards making every node
identifiable, but they are not the same. It's just a cryptographic
tool to keep a certain class of attackers from bypassing restrictions
that people can already make.

-- 
Pieter