network access rules evaluate network traffic’s source ip address, destination ip address, and ip protocol type to decide if the ip traffic is allowed to pass through the firewall. custom rules take precedence, and may override the internet firewall’s default state packet inspection.

    the ability to define network access rules is a very powerful tool. using custom rules, it is possible to disable all firewall protection or block all access to the internet. use extreme caution when creating or deleting network access rules.

    network access rules do not disable protection from denial of service attacks, such as syn flood, ping of death, land, and so forth. however, it is possible to create vulnerabilities to attacks that exploit vulnerabilities in applications, such as winnuke.

    click policy, and then select the policy rules tab. a window similar to that in figure 45 is displayed.

    figure 45 policy rules window

   

    it is important to fully consider logic behind the new rule before you add it. use the list in “network access rule logic list” to help you create logical rules.