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My query is related to broadband network deployment. I have a DSL modem connection provided by my operator. Now the DSL modem has a built-in NAT and DHCP server, hence it allocates IP addresses to any client devices (laptops, PC, mobile) that connect to it. However, the DSL modem also gets a public IP address X that is provisioned by the operator.

My question is

  1. Whether this IP address X provisioned by operator is an IP address that is directly on the public Internet?

  2. Is it likely (practical scenario) that my broadband operator will put in one more NAT+DHCP server and provide IP addresses to all the modems within his broadband network. In this case, the IP addresses allotted to the modem devices will not be directly on the public Internet.

Thanks in advance.

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migrated from Apr 9 '10 at 15:55

This question came from our site for professional and enthusiast programmers.

You'll probably get a better answer if you post on :) – Mr Roys Apr 9 '10 at 14:16
Not a programming question – Anonymous Apr 9 '10 at 14:27

I would normally expect your modem's outside address to be on the public internet. You might encounter multiple layers of NAT at a school, business, or other institution. There are a number of sites that will test your connection. One that comes to mind is ShieldsUp! at

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