On 05/30/2010 04:44 PM, Sabahattin Gucukoglu wrote:
BitTorrent is popular, yes. People at home *are* behind NAT boxes, with all
the usual pain that implies *. It's just that BitTorrent, being a
straightforward TCP protocol with no embedded payload addresses **, can operate
behind NATs, and those NATs can be configured either manually or automatically
by users or their client software ***. If the NAT should move to the ISP, it
seems possible that this is no longer true.
1. Bittorrent clients connect to each other via TCP. Each connection is
incoming at one end. Torrent clients mostly use UPNP to accept incoming
2. UPNP is an ethernet-level protocol (it uses UDP/IP broadcasts), so it
works only if the USER is on the public internet. Hence, NAT within the
user's network is now very different from NAT within the ISP's network.
That's why I said the wide popularity of bittorrent shows that USERS are
on the public internet.
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