Introduction

Some of us can remember a time when securing a network environment was a far easier task than it seems to be today. As long as every user had a password and the correct levels of file permissions had been set, we could go to sleep at night confident that our network environment was relatively secure. This confidence may or may not have been justified, but at least we felt secure.

Then along came the Internet and everything changed. The Internet has accelerated at an amazing rate the pace at which information is disseminated. In the early 1990s, most of us would not hear about a security vulnerability unless it was reported by a major magazine or newspaper. Even then, the news release typically applied to an old version of software ...

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