Putting Up a Wall Between the Dangerous Folks and Your Network

Putting Up a Wall Between the Dangerous Folks and Your Network

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The only new icon in the figure is the icon that Cisco uses to represent its firewall product, called a PIX Firewall. Regardless of the model or brand of firewall, the firewall forwards the packets that enter and exit the Internet connection. The firewall behaves like a router in that it forwards IP packets. But because the firewall sees all the packets passing over the Internet connection, the firewall can decide whether each packet should or shouldn't be allowed, based on the rules set up for the network. A network engineer would have to configure the firewall to tell it the information included in Table 18-1. The firewall will simply pass what is allowed and discard what is not.