Personal Firewalls

The purpose of a firewall is to filter inbound and outbound traffic to your computer or network. Information is sent through the Internet in packets of data, and these packets have sources and destinations. You become vulnerable to attack when you have no protections from all the various types of packets that are being sent to your computer. On the Internet, connections are made to open ports on your computer. As we discussed in Chapter 10, when you have an open port that anyone can reach on the Internet, you are potentially vulnerable to an attack. Your broadband cable or DSL connection leaves you wide open day or night to attack. Even your dial-up account leaves you open to attack, but the limited time you are connected via ...

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