Total relay bandwidth in the Tor network

https://metrics.torproject.org/network.html?graph=bandwidth&start=2012-06-12&end=2013-12-11#bandwidth

by Ihmahr • 13 years ago

114 38 13 years ago

metrics.torproject.org

For more historical perspective: https://metrics.torproject.org/network.html?graph=bandwidth&start=2008-06-12&end=2013-12-11#bandwidth

nly6• 13 years ago

There was a good overview of how the network is actively managed, and who is providing new relays and the most bandwidth, at Defcon 21:

https://www.youtube.com/watch?v=864FxA3jmHk

Ihmahr5• 13 years ago

Yes, I have been considering i2p, the 'garlic router' which seems to have hedged against a lot of attacks that could be possible on tor.

nly6• 13 years ago

I agree, I2P is interesting. I don't know why it doesn't get more press or support. According to the website some reps of the I2P team will be at 30C3 in 2 weeks time btw.

belorn5• 13 years ago

isn't i2p simply tor but with 2 hops instead of 3?

anonymousDan• 13 years ago

Given the need for critical mass, is there any way some or all of the advantages of i2p could be retrofitted to tor, or are the differences more fundamental?

belorn5• 13 years ago

For additional information: https://blog.torproject.org/category/tags/entry-guards

slashdotaccount• 13 years ago

According to the "Full Disclosure - The Internet Dark Age" paper (1) the N.S.A. can route a target who is using Tor into their "own" Tor network where they control all the nodes, thus compromising the security of the target. Does anybody knows how one can be sure that he is in the legitimate Tor network and not a fake one?

(1) http://cryptome.org/2013/12/Full-Disclosure.pdf

nly6• 13 years ago

The Tor consensus is digitally signed. That entire 'paper' looks like sensationalist garbage. A paragraph on each topic with no sources or analysis does not qualify as research.

kyboren3• 13 years ago

Agreed. As I wrote in another thread:

I also do not think their claims of Tor subversion hold water. From what I understand of Tor, directory information (including nodes' key fingerprints) is ultimately verified by the hard-coded keys of very few "trusted" operators of authoritative directory servers. So long as the Tor software isn't compromised, no MITM, regardless of where it's effected, will be able to subvert the user's circuit construction (of course, barring bugs in Tor and exploits higher up in the software stack). At least, that's my understanding.

However, I do assume they are very interested in capturing both short-term directory signing keys and the long-term keys which verify those short-term keys. This means the Tor servers listed as "dirservers" in src/or/confic.c, but especially the nodes tor26, dizum, Tonga, gabelmoo, maatuska, dannenberg, and Faravahar, as they appear located outside the US and so probably "game on" for NSA. I also assume NSA's "partners" will try the same with those authoritative directory servers in the US, which NSA would undoubtedly use to enhance their capabilities. Those who run authoritative directory servers need to be very careful (cough Appelbaum cough).

The paper's main conclusion, "NSA/GCHQ can surreptitiously selectively MITM users' Internet connections", appears to be valid (see FOXACID servers and NSA's "man-on-the-side" attack), but this is a well-known threat model.

In my non-professional opinion, the most likely way NSA/GCHQ would attack Tor appear to be through:

1) Honeypot nodes -- Tor relays which act normally, but silently record timing and circuit routing information ("circuit 2981: $253DFF1838A2B7782BE7735F74E50090D46CA1BC -> $1041213B53CCF586093BB65D9CC4BC0B9656EF17 @t=1386775503.00312")

2) "Upstream" data analysis of regular node connections -- build statistical models of likelihood of a client circuit routing from input node X to output node Y by observing timing of transmission rate bursts

3) CNE of non-US Tor nodes -- Pwn foreign nodes to turn regular nodes into honeypots

And so I wonder: it appears little can be done about 1) and 3) above what's already being done (other than emphasizing to relay operators that Tor relays should be run on an isolated system with as few open services as possible). Tor maintainers seem to see vulnerability to 2) as a fundamental problem with low-latency mixnets, and haven't taken steps (AFAIK) to complicate that analysis. Would it be effective to do something like the following?

1) Propagate relay-to-relay latency and jitter statistics along with client circuit data

2) Have each relay build a model of incoming latency and jitter statistics for each other relay

3) Associate each new client circuit on a relay with a latency and jitter bin selected uniformly at random from the models built in 2), excluding the model associated with the true incoming relay

4) Delay all packets in that circuit by the associated latency time, +/- jitter calculated from a probability distribution created in the associated model of 2)

This might be in combination with a change that removes or smooths bandwidth spikes by inserting dummy traffic between relays.

With both strategies, a) latency would be worse, and b) total available bandwidth would be lower. It looks like there's considerably more advertised bandwidth than there is used bandwidth, so b) might be OK. But a) might be a big problem for usability.

One more harebrained scheme: have each relay pick a few 'buddy' relays whose total advertised available buddy bandwidth sums to ~50% of this relay's estimated bandwidth. For each new client circuit, flip a coin and determine whether this circuit's traffic will be forwarded directly, or given to a buddy to forward. Similarly, the buddies each do the same with this relay. Associate 'chosen' client circuits with a buddy that tends to make a symmetric and smooth bi-directional data flow between the buddies.

OK, stream of consciousness over... I really got off on a tangent. I'm very interested to see why my lame schemes won't work, so please point out why I'm wrong (as I assume I probably am) :).

owenmarshall5• 13 years ago

Does anybody knows how one can be sure that he is in the legitimate Tor network and not a fake one?

I'm a bit uncertain that document is completely credible - it makes some claims that appear to be very wild, even given what we've seen so far.

But let's assume they're right about their Tor claim. Even if the NSA places you on a controlled Tor network, I could still read my gmail because the NSA would have to try to get around Google's SSL.

Some bad endpoints have been known to try and MITM SSL before, but always with self signed certificates, so if the user messed up it was down to them.

Of course, if our endpoints are run by the NSA, and the NSA have pressured other CAs to sign *.google.com, we can only depend on cert pinning. But it's the NSA, so how do we know that they haven't already backdoored my browser to change the pinned fingerprints...

But at the end of the day, the latest I'd heard from the Snowden revelations is that Tor is a major thorn in the NSA's side, so I'm inclined to believe that over this breathless PDF that makes all sorts of outlandish claims.

EDIT: From that PDF:

When the DSL connection is established a covert DHCP request is sent to a secret military network owned by the U.S. Government D.O.D. You are then part of that U.S. D.O.D. military network, this happens even before you have been assigned your public IP address from your actual ISP.

That stretches the bounds of credulity - it assumes that a giant government-mandated conspiracy exists between ISPs, device manufacturers, networking developers... even with what we've seen so far it's impossible to swallow.

bdb• 13 years ago

The entire premise of that paper is misguided. It's fairly common for large providers[1], e.g., BT, Sprint, T-Mobile, to use several of the non-Internet-connected DOD /8s for management addresses, once they've exhausted RFC1918.

[1] http://seclists.org/fulldisclosure/2012/Feb/319

yuvadam• 13 years ago

You can read your Gmail over HTTPS, but Tor hidden services generally do not use SSL/TLS (since they _are_ the exit node for that connection).

bernatfp• 13 years ago

I don't like how this title oversimplifies the causes of growth to be the NSA scandal. I guess Silk Road also played an important role in this increase and it is not mentioned.

Ihmahr5• 13 years ago

How did silk road add more bandwidth to the network? Also, SR was way before Snowden.

ressaid1• 13 years ago

The only way to access Silk road was through TOR

alan_cx• 13 years ago

I wonder how much is to do with the Piratebay, and circumventing blocked sites?

john-p• 13 years ago

loading speed is still too slow for daily use really.

dublinben• 13 years ago

Have you done your part to improve that by contributing a relay?

belorn5• 13 years ago

Using tor on a daily basis depend on how people surf the web.

If you are one of those people who click on news article all day long, maybe read comments, then the added latency do not really do anything. You go to HN, open in new tabs all the interesting articles you want to read. By the time you reach the end of HN front page, the first page is loaded.

Total relay bandwidth in the Tor network

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