[tor-bugs] #4185 [Tor Bridge]: Bridge easily detected by GFW

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#4185: Bridge easily detected by GFW
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 Reporter:  hrimfaxi    |          Owner:                    
     Type:  defect      |         Status:  new               
 Priority:  normal      |      Milestone:                    
Component:  Tor Bridge  |        Version:  Tor: 0.2.3.5-alpha
 Keywords:              |         Parent:                    
   Points:              |   Actualpoints:                    
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 I tried to setup a bridge relay in USA and access it from China. But it
 seems their communication can be detected very soon and got filtered by
 the GFW.

 At first I thought it's because the address of my bridge relay got
 published and leaked to the GFW staffs. But even I set
 PublishServerDescriptor to 0 in the torrc of bridge the blockade still
 occurs.

 Every bridge relay I setup can only live 1~10 minutes before they got
 blocked and were no longer accessible in China, used the telnet utility
 for confirming that.

 When the blockade occurs, not only bridges but also normal relays were
 blocked.

 If I change the bridge port (like from 443 to 444) then it can be
 connected again before the next blockade occurs after 1~10 minutes.

 I tried the both stable 0.2.1.x and alpha (0.2.3.5-alpha) release of tor
 and they were all vulnerable.

 Was it a new attack to block tor traffic?

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/4185>
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