How to Find the IP Address of the Firewall on My Network

The firewall on a local area network is responsible for blocking unwanted traffic from entering or leaving the network. Part of the firewall's job is to perform NAT--network address translation--to allow all of the computers in the network to access the Internet at the same time. Servers running inside NAT environments are difficult to connect to because they cannot receive traffic directly; clients must send their traffic to the firewall instead.

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Firewalls increase security but introduce additional complexity.

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Log in to one of the computers in the local area network that is protected by the firewall.

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Open a Web browser.

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Type in the URL of one of the many free address-checking services. (See Resources for examples.)

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Connect to the website.

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Read the page and find your Internet protocol address: This is also the IP address of your firewall's public interface.