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We have a socket application (client and server) which runs in our environment.

In our client site they're using NAT. When I try to connect my client (from a NATed IP in client's NATed environment) to a server in the client's NATed environment, it fails.

What are the things to be checked?

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up vote 0 down vote accepted

You'll have to ask your client's system administrator to add rules to their router/firewall infrastructure.

For example the simplest case: if the internal server is listening on TCP port 9876 on, the external public IP address of the client's router should allow and forward all traffic to that port of the server's internal IP address.

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So it is not in my hands (i.e) sockets ,so the router will do things – karthik Feb 24 '10 at 9:58
yes, you can't change a network's behavior just by adding something to your endpoint (client/server) software. – splattne Feb 24 '10 at 10:16
The original poster says that both client and server are in "client's NATed environment", suggesting they're both on the 'inside' -- so really you need to discuss the issue with someone who knows that network, to understand why what you're trying isn't working. – jrg Feb 24 '10 at 12:32
@jrg Hmm, actually the original post was a little confusing and ambiguous. Since the author of the post mentioned NAT I was sure he meant accessing the server from the outside. Why mention NAT if this was an internal problem? – splattne Feb 24 '10 at 12:53

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