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1 edit | Experience with another ISP I found that enabling BitTorrent encryption (PE+MSE, which has been out for more than a year), did extend the time it took for Comcast+Sandvine to detect the protocol and interrupt it. This is probably because (I'm guessing) the additional handshake broke one signature and allowed the conversation to enter the Tit-for-tat (file transfer mode). Now past the handshake, then only after enough packets were observed (still guessing), they had enough information to determine that the protocol was BitTorrent.
BitTorrent "encryption" is a bit of a misnomer. It's a simple cipher, so beyond the handshake, it adds no overhead. Unfortunately, it also means that 1) it's easy to crack, and 2) even if not cracked, you can still pretty much detect it just from packet lengths (a REQUEST is always the same size, a HAVE is always the same size, and etc.) and order (HAVE precedes INTERESTED, UNCHOKE precedes REQUEST, and etc.).
Ironically, this also means that Deep Packet Inspection is not needed to interfere with it.
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Robb Topolski -= funchords.com =- Hillsboro, Oregon
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