Such filtering for pirated material already occurs on sites like YouTube and
Microsoft’s Soapbox, and on some university networks.
Network-level filtering means your Internet service provider – Comcast, AT&T,
EarthLink, or whoever you send that monthly check to – could soon start sniffing
your digital packets, looking for material that infringes on someone’s
copyright.
“What we are already doing to address piracy hasn’t been working. There’s no
secret there,” said James Cicconi, senior vice president, external & legal
affairs for AT&T.
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In defense, the open source community has created tunneled packet encryption and the randomization of ports as well as implementing anonymity strategies - all of which makes network usage less efficient and further bogs down the net for everyone.
In the end, even the http protocol (used by your web browser) can be used to build an effective p2p network, therefore the ISP's will have to basically shut down the whole damned thing if they are ever to succeed at filtering out p2p traffic.