FWD: [IP] Encrypting Bittorrent to take out traffic shapers

[Dave Korn]

Alexander Klimov wrote:
> On Tue, 7 Feb 2006, Adam Fields wrote:
>> Over the past months more Bittorrent users noticed that their ISP is
>> killing all Bittorrent traffic . ISP?s like Rogers are using bit-
>> shaping applications to throttle the traffic that is generated by
>> Bittorrent.

>> A side note is that they're using known insecure encryption methods
>> as a cpu tradeoff because it doesn't matter if the traffic is
>> decrypted eventually, as long as it can't be revealed in realtime.
>> That's possibly shortsighted, but still interesting.
>
> Since one can easily encrypt >60 Mb/s with AES on a modern computer it
> does not matter what algorithm to use (unless, of course, you have a
> wider than 60 MB/s connection).

  Ah, but you haven't allowed for the fact that the ISP has to do this for 
/all/ the traffic from /all/ of their customers if they want to know if it's 
BT or not.

> BTW, if ISP really wants to slow down bittorrent it can use some other
> methods: there is usually constant port (6881, IIRC), and quite
> specific communication patern.

  Indeed, they're likely to find a traffic-analysis method of doing this 
sooner or later, and then they won't have to bother about the encryption.

      cheers,
         DaveK
-- 
Can't think of a witty .sigline today.... 




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