4 ms·

Hasn't Tor failed to meet its goal so far? With only 900 exit nodes, it's totally feasible to block them all, which is exactly what China has done. If Tor isn't

by jordigh 10y ago

Hasn't Tor failed to meet its goal so far? With only 900 exit nodes, it's totally feasible to block them all, which is exactly what China has done. If Tor isn't usable for hopping over the GFW, it hasn't yet fulfilled its true potential, has it?

AgentME 10y ago
Hiding the fact that you're using Tor isn't one of the main goals of Tor.
- jordigh 10y ago
  "Tor provides a gateway to the free Internet, bypassing most mediums of censorship that may be imposed by someone, like for example oppressive regimes." People sure seem to believe that getting around censorship is one of the main goals, though.
  - AgentME 10y ago
    Tor does have private bridges into the network that you can request access to, which is their solution to this issue.
- adamfisk 10y ago
  It's not a matter of hiding the fact that you're using Tor, it's a matter of whether it bypasses censors or not. There's a big difference between those two. Even if a censor is able to detect that an individual node is running Tor, that doesn't mean they can globally detect all nodes and then block them. Tor's user numbers in China in particular are very low simply because it's just straight blocked. Private bridges and pluggable transports can get around that, but they're just not used at scale because that's just too challenging for ordinary users.
witty_username 10y ago
There are bridges that can be used to connect to the Tor network.
apk17 10y ago
The way china is blocking tor is completely independent on the number of nodes. They even go and detect the traffic to bridges. The problem is more like that tor relies on a few directory authorities and the only protection they have is geographic distribution and the public outcry should a set of nation state go actually seize them.
- nbraud 10y ago
  > The problem is more like that tor relies on a few directory authorities and the only protection they have is geographic distribution and the public outcry should a set of nation state go actually seize them. Seizing the DirAuth wouldn't achieve anything useful: all the data that the DirAuth has access to is a matter of public record (literally, the role of the DirAuth is to collect that data, sign it cryptographically and vote on it). A group of nation-states looking to attack Tor this way would need to stealthily subvert a majority of the DirAuth, and manipulate the network consensus in a way that is both hard to detect and allows them to deanonymise users; that's very far from trivial.
  - apk17 10y ago
    I don't know the timeout for that, but after some time no tor node would work without the dirs being present, or being manually pointed to new ones. The question is whether someone would want to subvert or rather just shut down the tor network.
    - nbraud 10y ago
      Ah, ok, you were referring to the DoS vector. Yes, a simultaneous seizure of the DirAuth would do that, breaking Tor relays and clients until the software is updated (the list is in src/or/config.c if you are curious). On the other hand, it's a move that would require international cooperation <i>and</i> cost lots of political capital, whose only result would be a temporary (but global) DoS.

by jordigh 10y ago

AgentME 10y ago

Hiding the fact that you're using Tor isn't one of the main goals of Tor.

jordigh 10y ago
"Tor provides a gateway to the free Internet, bypassing most mediums of censorship that may be imposed by someone, like for example oppressive regimes." People sure seem to believe that getting around censorship is one of the main goals, though.
- AgentME 10y ago
  Tor does have private bridges into the network that you can request access to, which is their solution to this issue.
adamfisk 10y ago
It's not a matter of hiding the fact that you're using Tor, it's a matter of whether it bypasses censors or not. There's a big difference between those two. Even if a censor is able to detect that an individual node is running Tor, that doesn't mean they can globally detect all nodes and then block them. Tor's user numbers in China in particular are very low simply because it's just straight blocked. Private bridges and pluggable transports can get around that, but they're just not used at scale because that's just too challenging for ordinary users.

witty_username 10y ago

There are bridges that can be used to connect to the Tor network.

apk17 10y ago

The way china is blocking tor is completely independent on the number of nodes. They even go and detect the traffic to bridges. The problem is more like that tor relies on a few directory authorities and the only protection they have is geographic distribution and the public outcry should a set of nation state go actually seize them.

nbraud 10y ago
> The problem is more like that tor relies on a few directory authorities and the only protection they have is geographic distribution and the public outcry should a set of nation state go actually seize them. Seizing the DirAuth wouldn't achieve anything useful: all the data that the DirAuth has access to is a matter of public record (literally, the role of the DirAuth is to collect that data, sign it cryptographically and vote on it). A group of nation-states looking to attack Tor this way would need to stealthily subvert a majority of the DirAuth, and manipulate the network consensus in a way that is both hard to detect and allows them to deanonymise users; that's very far from trivial.
- apk17 10y ago
  I don't know the timeout for that, but after some time no tor node would work without the dirs being present, or being manually pointed to new ones. The question is whether someone would want to subvert or rather just shut down the tor network.
  - nbraud 10y ago
    Ah, ok, you were referring to the DoS vector. Yes, a simultaneous seizure of the DirAuth would do that, breaking Tor relays and clients until the software is updated (the list is in src/or/config.c if you are curious). On the other hand, it's a move that would require international cooperation <i>and</i> cost lots of political capital, whose only result would be a temporary (but global) DoS.