[liberationtech] CJDNS hype

[Gregory Maxwell]

On Sat, Jul 13, 2013 at 12:36 PM, Mitar <mmitar at gmail.com> wrote:
> For me it seems far from something which would be resistant to any
> adversary trying to prevent communication from happening. It seems to
> me that it just ignores many of issues with DHTs and routing in
> overlay networks put out in research literature until today. Which is

DHT's are basically a complete joke when it comes to attack
resistance, and so it's with much face palming that I've endured near
constant suggestions to "Use a DHT!", often in completely inapplicable
contexts, from people whos only exposure to distributed systems is
DHTs.  It's basically a running joke in the Bitcoin development
community at this point.

That said CJ is, in fact, aware of these issues— and CJDNS is at least
intended to be resistant to sibyl attacks under some assumptions (I
believe the main assumption is that you choose honest peers for your
transport links (and that your honest peers also do so), because it
isn't simply a topology blind DHT).  The system is setup to require
manual peering, so it isn't just a handwave— it's how you're expected
to use it.

(Now, how strong that requirement is isn't clear to me, e.g. how does
your security fall off as a function of distance to honest nodes— or
how realistic even the weakest form of that requirement is in
practice, e.g. can even a spherical-technical-expert manage to
reliably pick non-sybil peers— is another question.)

Some of the other concerns about CJDNS is that its not— by itself— an
anonymity network. Its anonymity properties are weaker than TOR's, for
example. Though it may be the case that the composition of CJDNS and a
high latency (/CBR) mix network might better address the spectrum of
needs, there is still the risk that people may misunderstand what is
actually being provided.