Nextgen G* Traffic Analysis Resistant Overlay Networks (re Tor stinks)

[grarpamp]

Various wrote:

> "seconds of traffic" refers to the global buffer space
> and time required for *PA find a solution within it.

> I've wondered whether it's just that they need lots of users for cover
> traffic. That _was_ a major factor in opening Tor to the public, instead
> of restricting it to government users. But that seems unlikely, now,
> given that the NSA etc could easily run enough bots on hacked servers.

> My guess is that the main reason for them to get as many users as they can is to justify funding. Hell, maybe they even get a percentage of funding directly proportional to number of users/network size.

> The Tor rationale for requiring low latency was to make it more
> user-friendly and also thereby increase (innocent) traffic.
> Unfortunately that came at the cost of easier traffic analysis, as only
> the traffic passed within the last 4-5 seconds need be considered. They
> tried to balance that out - more traffic plus greater usability vs
> easier analysis

> Initially the main reason was to increase traffic, in order to make traffic analysis harder.

https://metrics.torproject.org/

Tor doesn't use traffic fill, many seem to talk about
that from "omg bandwidth" rather than how it could
potentially be used. A net that uses fill doesn't necessarily
have to be full of 10k-10M+ whatever many users to achieve
TA resistance. And even a fill net of just 100 nodes could work
well for whatever users it does or doesn't have.
The tor network can be quite sparse with voids of low traffic / users.
Tor did traffic weighting probabilities to try to counter some of the
single user paths that would obviously otherwise be created by
pure random routing through such voids. However adversaries
can still describe analysis and attacks against users passing
strictly through only the most saturated of nodes, it's a bit harder,
with fewer options, but still doable.
Interestingly, such a weighting system is a gravity well...
"more users" just distribute themselves into its available
density slots... thus adding "more users" to the network
doesn't necessarily make that type of network more secure,
they just increase the physical size of the blackhole.
Whether the net has 1k or 1M users, they're all going
to be within some standard deviation of density that
they themselves create among the well... from 1.0 when links
are saturated in the singularity, out to 0.0 in voidspace.
Users have no real guarantee they will fall into some
feelgood safety slot, say around >=0.85, nor does it
matter since as above, adversaries can still attack 1.0.
A fill network can more readily use random routing,
and its smaller volunteer node operators are happier since
they have a more equal chance to carry traffic.
Fill or non fill, random or not, your path is still subject to both
the worst, and the sum of, all the headroom capacities and latencies
it traverses... unless you start getting into distributing signalling
for that around the network, which is probably a complex task.
Tor allows users to pick empty paths if they don't care about voids.
Any next generation network should have some user facing path
selection knobs to handle censorship and anti-Sybil subscriptions.
Also, if they know their endpoints (a local: chat friend, exit website,
hidden server), a fill network might allow users to better play off
jurisdictional spy buffers and performance bets by selecting local
nodes only... whereas a non fill gravity network might leave voids
in their region, that the less advanced adversaries in their
region might otherwise more easily exploit, thus prohibiting
use of local selections to achieve better latency performance,
ie: for messaging during a regional / local protest, or for much
faster local / guerrilla links for filesharing, etc. This notion
of potentially staying local under a fill network, versus being
forced to go path out through the gravity well, may also reduce
load over virtual intercontinental paths, ie: the network might
begin to naturally emulate backbone tiering but with no additional
spy buffer risk due to the entire network fill. The Phantom network
had some free thinking into developing for users to make such
selections metrics over its node set. Tor still blankets users
who ask about selecting nodes... with "no", and they secret up
anti-Sybil bad-relay ops under "yep tor has that" "dirauths are trusted"
"no worries" advertising that tend to keep independant user based
efforts to do such things from starting up.