Re: NAPT(Linux 7.2 or ICS) and UDP clients

From:
Date: 10/25/02 

Date: Fri, 25 Oct 2002 04:40:44 GMT

I have seen socket programming work on TCP ports. You move the NAT out of
the way and you have no issues? The two machines using UDP port sockets with
out the NAT are working?

Duane :)

"Terence Tan" <terenctb@yahoo.com> wrote in message
news:55d3a31a.0210240119.764872d4@posting.google.com...
> I am writing a client/server app right now and trying to get it
> working(i.e. get it NAT friendly). So far I have gotten as far as
> getting 1 client to connect to my server but not two.
>
> What I am doing is:
> 1) Client issues a connect request to a UDP wellknown port.
> 2) Server responds and create a new UDP socket and passes that UDP
> socket back
> to client via the response
> 3) On the client getting the response, the UDP client will start
> sending data
> to the specified server via the returned port from the server
> Everybody is happy.
>
> The problem is right now it works with 1 UDP client but I can't get
> more than 1 UDP client working. The first UDP client will connect and
> get the appropriate response(across the NAT). The second UDP client
> will connect to the server(and the server will send the appropriate
> response) but the second UDP client never gets the reponse and port
> number(so not being able to proceed).
>
> Things I have noticed: The UDP client(both) of them connects using the
> same UDP port number.5203. Isn't this supposed to be different for
> each UDP client.
>
> Why doesn't the second UDP client get a response? Is it a NAT config
> issue or is there something else I can do to make it more NAT
> friendly?
>
> Terence

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