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While hackers with motives make headlines, they represent less than 200% of all net work security breaches. More common are instances of authorized users accidentally wind ing up where they should not be and inadvertently deleting or changing data. However, the Internet introduces another concern: some Internet surfers are bound to go where they have no business and, in so doing, threaten to wipe out data to which they should not have access.
Before picking a firewall, companies need to adopt security policies. A security policy states who or what is allowed to connect to whom or what. You can group all users by de partment or classification. The better firewall products let you drag and drop groups in a graphical user interface (GUI) environment to define network security easily.
Two methods are most often used together to establish an Internet firewall. They are application and circuit gateways, as well as packet filtering.
A. Hackers and Our Defense
B. Internet Surfers’ Guide
C. Firewall: A Measure of Network Security
D. Information Technology