[tor-dev] Why the seeming anticorrelation between obfs3 and vanilla bridges in metrics graphs?

[Karsten Loesing]

On 23/10/14 19:32, David Fifield wrote:
> In the past few months of bridge user graphs, there is an apparent
> negative correlation between obfs3 users and vanilla users: when one
> goes up, the other goes down. If you draw a horizontal line at about
> 5500, they are almost mirror images of each other. I don't see it with
> any other transport pairs. Any idea why it might be?

Hi David,

I briefly looked at the raw data behind this graph, but didn't find any
obvious problems with the algorithm.  I'm running out of time now, but I
can share some preliminary results in case you want to dig deeper:

 -
https://people.torproject.org/~karsten/volatile/bridge-users-obfs3-or-mean.png
is the graph that you posted with a third line for mean values.

 -
https://people.torproject.org/~karsten/volatile/bridge-responses.csv.xz
contains numbers of responses (for requested consensuses) by bridge,
transport, and time interval.

 -
https://people.torproject.org/~karsten/volatile/bridge-responses-by-transport.pdf
shows responses by transport.

 -
https://people.torproject.org/~karsten/volatile/bridge-responses-over-time.pdf
shows only <OR> and obfs3 responses over time.

 -
https://people.torproject.org/~karsten/volatile/bridge-responses-or-by-fingerprint.pdf
shows only <OR> responses higher than 1000 by fingerprint.

 -
https://onionoo.torproject.org/details?fingerprint=231E2DE81DC4314F2035D2C0D0D043A425FF8999
is the bridge reporting those high numbers for <OR> responses.  Is
PacificSunset maybe one of the bundled bridges?

That's all.  Maybe it helps?

All the best,
Karsten