On Tue, 10 Sep 2013 14:17:12 +0000, George Kadianakis wrote:
Hey Yawning (and tor-dev),
a topic that we will soon need to consider seriously is rate limiting of pluggable transports. For example, Obfsproxy at the moment does not understand rate limiting and will happily read and write as many bytes as needed.
My first reaction: Why should it care? As long as it only reads from the input as long as the output isn't/wouldn't be blocking, all is fine with the transport - it behaves like the direct TCP bridge protocol.
...
For example, I'm kind of sad about this approach, because it requires little-t-tor to do all the hard work of monitoring bandwidth usage and giving out intelligent rate-limiting orders.
So, why not? I think it is easier to implement that in one place than needing to reimplement it in any pluggable transport again (or at least once per implementation language).
After all, tor is the one who sees the total traffic anyway, and thus is in a unique position to throttle in a fair way, for any definition of 'fair'.
And it also means that we can throttle the regular bridge protocol as well. Which actually makes me wonder: Why do you expect that we need this kind of rate-limiting?
Andreas