Re: peer to peer messaging

First of all, WOW!!! This was a great reply... thanks Chris for the
valuable information.
One question does come to mind when reading the two sections below:

> For example a packet from my machine might have source IP
> aaa.bbb.ccc.ddd, and source port 3872 (randomly allocated when it attempts to
> make the connection) and destination address 209.249.116.141 and port 80.
> Packets from the sever to my laptop would have those reversed. Here, "my" IP
> address (aaa.bbb.ccc.ddd) is allocated by the relevant networking authorities,
> and has been assigned to me, and any machine anywhere on the network can
> address my machine using that address.


> When it sees a packet emanating from my laptop (or anywhere else in the NAT-ed
> subnet that it manages), it changes that packet so that it appears to come from its
> own IP address, aaa.bbb.ccc.ddd, and from a port number that it has temporarily
> allocated. It remembers that it is now managing a NATed connection for that
> IP/port. The server sees this packet just as before, and replies just as
> before. The reply ends up back at my router, which inspects the packet, and
> sees that the destination IP/port are for a connection that it knows about. It
> looks that data up in its internal list of connections, and finds the IP/port
> that my machine originally used. It changes the incoming packet to use that
> destination IP/port and sends the packet on to my machine.



So for this example, the server is responding by sending the data to
address aaa.bbb.ccc.ddd and source port 3872 which would be forwarded
to the local machine from the router. How long is this port dedicated
to forwarding to the local machine?

.

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