>> It's doable, but I don't think BT does that now... it just assumes certain >> ports are open... > >I don't remember how it works, but I've seen some machines running it >(and sharing) from behind a NAT. > >If it sends a "here I am", the connection could be done from this point >- once it begun inside. I don't know if bt is smart enough though. Yes, exactly. The "here I am" is not required to do the download part. It is needed to keep a NAT path, and access list open so an incoming request to my machine will be received. The "here I am" message basically says "I'm listening on port xxxx at address 1.2.3.4". Then, when somebody else wants to down load a file and they go to a BT aware server, that server might tell them... "Yes, go get it from TCP 1.2.3.4:xxxx". As long as my NAT translation AND access list still permit that specific traffic, all should be OK. Keep in mind the "Here I am" message should not actually embed the port number nor IP address. Each of those may be changed by NAT along the way. Instead the BT server will see the incoming address from my machine, and the port. As I say, it's doable, I just don't know enough of the internals of BT to say for certain. Since my firewall access lists are dynamic, in my case, regardless of NAT Don
