Chapter . Firewalls

Protecting the Perimeter

As more computers connect to public networks, and as their employees connect to work through the Internet, opportunities increase for malicious attacks from hackers and saboteurs. The same applies to internal corporate networks, in that companies must protect their data centers and computing resources from internal and external attacks.

News stories often tell of websites being broken into, computers being erased, corporate data being stolen, and lethal viruses destroying computer systems. With the number of home users taking advantage of broadband “always-on” networks, hackers and data thieves have a whole playground of unsuspecting exposed home networks to tamper with.

Network attacks can occur for a ...

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