Coming soon to a network near you:
software for blocking file-sharing programs like Napster and Gnutella.
If the RIAA wins in court, such software may be necessary for ISPs wanting to
defend against litigation. Of course, it's unlikely to be a permanent
solution; only the latest round in an escalating arms race leading to more
obscure and intentionally cryptic protocols and countermeasures.
because it uses the fundamental characteristics of the protocol itself in
addition to relying on default port blocking, PacketHound is more difficult
to bypass. When PacketHound is in monitoring mode, users are completely
unaware of its presence. When it is in blocking mode, it kills unwanted
activity by issuing a reset packet to the requesting machine; the user sees
only a "connection reset by host" message.