The lowdown on personal firewalls
What is it?
A personal firewall, more properly a single-computer firewall, is software only and can be less complicated than dedicated firewalls. But it should be highly configurable, so you can tailor the protection to the threat level and the sensitivity of the data stored on the computer. Antispyware utilities aren't firewalls but provide important extra protection.Why do I need it?
Because the Web is a dangerous place, as are many large networks. Mobile workers, telecommuters or professionals who must connect to a variety of networks all need personal firewalls on their computers. Workstations storing especially sensitive data or being used for critical tasks might need to be isolated from a local network.Must-know info?
Installing a personal firewall is generally easier than managing one that protects an entire network, but it must still be configured with skill.
Except in homes, firewalls are seldom used to run Web pages or perform other Web services, so most ports can be routinely blocked, perhaps leaving open only a few, such as the one needed for File Transfer Protocol (usually Port 21).
Many personal firewalls can be configured to allow only specific programs to access the Web and to block the transmission of key information. Determine just what information, such as e-mail addresses or phone numbers, is on the computer and configure the firewall to protect that data unless it's encrypted or needed for a secure site.