What Does the Software Do?

The Personal Firewall protects an individual computer from network traffic that can cause harm to that computer. It does this in a variety of ways, which can be summarized into three categories of firewall rules:

1. Allow: The Personal Firewall Allows some traffic to flow. This is usually traffic that is known to be "safe", usually because you have defined it, application by application, to be "safe." Examples of traffic normally classified as safe include Outlook, Internet Explorer, Netscape Navigator, Outlook Express, and other common networking and communications software.

2. Block: The Personal Firewall Blocks some traffic. This is usually traffic that is known to be problematic or dangerous to your computer.

3. Ask: The Personal Firewall Asks whether incoming and outgoing traffic is allowed to access your computer or an organization’s network resources. When you run the Firewall, it initially asks you whether to permit your applications to access network resources. Optionally, it remembers your responses, so that you do not have to tell it again, for example, that you plan to use Internet Explorer or Netscape Navigator.

By using firewall rules, the Personal Firewall can systematically Allow, Block, or Ask about what action to take on incoming traffic from specific IP addresses and ports. The configuration of those rules with other security settings provides a security agent that protects your computer.