[tor-talk] Vodafone DE throttles connections to the Tor network

[Dan Snow]

Hi,

The ISP Vodafone Germany ('provided by GCHQ') is slowing down network speed extremely when trying to connect to the Tor network. Although advertising that there exists no DSL throttle [www.vodafone.de/dsl/dsl-drosselung.html] it is becoming more and more difficult to download the required directory information at the beginning ["Establishing an encrypted directory connection"]. Often this is stopped by timeout. 
"24.04.2015 01:10:41.335 [NOTICE] I learned some more directory information, but not enough to build a circuit: We need more microdescriptors: we have 29/6587, and can only build 0% of likely paths. (We have 0% of guards bw, 0% of midpoint bw, and 0% of exit bw.)"

The highest download speed is then at 4-6 kB/s or in better times at 15-20 kB/s. This way it is impossible to use the Tor network with Tor Browser to open a text-based site with html or to download e-mails with Torbirdy in Thunderbird. At the same time connections without Tor (Browser, ftp, torrent download) are working with speeds up to 1.5 MB/s. 

The throttling occurs using the latest Tor Browser versions on Windows or Linux systems, also when connecting with obfs3. The connection to the Tor network seems to work 'uncensored' if I use Tor Browser inside Tails with the preference of changing the MAC address. 
So, I would assume that the device's MAC address and / or the IP address which is almost always the same (provided by the router, although there are three or more different users), is used to block connecting to the Tor network.


"17.01.2015 00:17:19.658 [NOTICE] Bootstrapped 10%: Finishing handshake with directory server 
17.01.2015 00:18:57.352 [NOTICE] Delaying directory fetches: No running bridges 
17.01.2015 00:19:02.760 [NOTICE] Bootstrapped 15%: Establishing an encrypted directory connection 
17.01.2015 00:19:02.806 [WARN] Proxy Client: unable to connect to x.x.x.x:xxxxx ("Connection refused") 
17.01.2015 00:19:02.807 [WARN] Proxy Client: unable to connect to x.x.x.x:xxxxx ("Connection refused")"



With separately provided bridges [https://bridges.torproject.org/options] Tor Browser is working fine.
[May 15, 2015] Today's direct connection to the Tor network: downloading with 20-30 kB/s; downloading the latest version of Tor Browser here resulted in a corrupted file.
With custom bridges the download speed is around 600-1200 kB/s.


Vodafone seems also to learn these non-published bridges. I had three different bridges in "Tor network settings / enter custom bridges", and after a period of uncensored connections two of three bridges are blocked now:
"30.06.2015 05:31:34.228 [NOTICE] Bootstrapped 10%: Finishing handshake with directory server 
30.06.2015 05:31:34.229 [NOTICE] Bootstrapped 15%: Establishing an encrypted directory connection 
30.06.2015 05:31:34.230 [NOTICE] Bootstrapped 20%: Asking for networkstatus consensus 
30.06.2015 05:31:34.230 [NOTICE] new bridge descriptor 'Unnamed' (fresh): XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX~Unnamed at xxx.xxx.xxx.xxx 
30.06.2015 05:31:34.230 [NOTICE] I learned some more directory information, but not enough to build a circuit: We have no usable consensus. 
30.06.2015 05:31:34.230 [NOTICE] new bridge descriptor 'xyz' (fresh): XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX~xyz at xxx.xxx.xxx.xxx 
30.06.2015 05:31:34.231 [NOTICE] I learned some more directory information, but not enough to build a circuit: We have no usable consensus. 
30.06.2015 05:32:30.385 [NOTICE] Closing no-longer-configured Socks listener on 127.0.0.1:9150 
30.06.2015 05:32:30.385 [NOTICE] DisableNetwork is set. Tor will not make or accept non-control network connections. Shutting down all existing connections. 
30.06.2015 05:32:30.385 [NOTICE] Closing old Socks listener on 127.0.0.1:9150 
30.06.2015 05:32:30.385 [WARN] connection_connect_sockaddr(): Bug: Tried to open a socket with DisableNetwork set. 
30.06.2015 05:32:30.385 [WARN] Problem bootstrapping. Stuck at 20%: Asking for networkstatus consensus. (Network is unreachable; NOROUTE; count 1; recommendation warn; host XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX at xxx.xxx.xxx.xxx:9001) 
30.06.2015 05:32:37.108 [NOTICE] Delaying directory fetches: DisableNetwork is set."



I wouldn't have assumed that communications without surveillance are becoming that difficult in Germany. A lot of countries is developing legislation that makes encryption illegal or nearly impossible now.   


Dan







GPG key information:
pub 4096RSA/EC630522 2015-07-14 [expires: 2016-07-14]