BitTorrent protocol encryption
Protocol encryption (PE), Message stream encryption (MSE), or Protocol header encrypt (PHE) are related features of some peer-to-peer file-sharing clients, including BitTorrent clients. They attempt to make traffic harder to identify by third parties including internet service providers (ISPs).
MSE/PE is implemented in Azureus, BitComet, BitTornado, Deluge, Halite Client, KTorrent, Mainline, µTorrent, Transmission (v0.90) and rTorrent. PHE was implemented in old versions of BitComet. Similar protocol obfuscation is supported in up-to-date versions of some other (non-BitTorrent) systems including eMule.
Purpose
Peer-to-peer file-sharing traffic makes up more than a third of total internet traffic. Some ISPs deal with this traffic by increasing their capacity whilst others use specialised systems to throttle (i.e. slow down) BitTorrent traffic. Obfuscation and encryption make traffic harder to detect and therefore harder to throttle. These systems......