Firewalls

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6. Firewalls

Firewalls provide a means to section off certain systems from the rest of the Internet and allow only certain types of communication through the firewall.  Typically companies use them to put a “wall” up between their company and the Internet.  Users inside the firewall may be restricted to access only systems inside the firewall.  Likewise, users and systems outside the firewall may be restricted to only certain parts of the Intranet (inside the firewall).  This greatly reduces the security threat from unknown persons out in the Internet. 

Consider using a firewall where you have sensitive data such as grades, payroll or other administrative information.  For a list of firewall software see http://www.alw.nih.gov/Security/prog-firewall.html.