The All-New Switch Book: The Complete Guide to LAN Switching Technology, Second Edition

14.1. Network Security Overview

We've all heard horror stories of security breaches that have cost time, money, or loss of personal or corporate business information similar to the following real-life examples:

• An architect had all of his important data erased by a disgruntled employee. Apparently while looking at the Classified ads in the Sunday paper,^[] she saw an ad for the company she worked for that listed a job description exactly matching her current duties. She decided that the company intended to fire her and was trying to fill her position before they did. She went into the office, logged onto the computer, and deleted all of the blueprints (several years' worth) that the architect had stored. The architect reported that the total loss of data was equal to several million dollars.^[]

  ^[] The fact that she was looking might indicate that she was intending to leave anyway.

  ^[] With data that amounted to that much money, you would think that there would have been some sort of backup, but there wasn't. The architect ended up paying someone to recover the data, and I think that most of it was recovered.

• In late 2001, a malicious virus was released called the Nimda Virus. This virus (a "worm") was spread via e-mail attachment. Once an end user opened the attachment, the worm infected the computer, and then used that computer to assist in locating vulnerable websites to attack. This approach allowed it to reach internal sites behind firewalls. The virus also would use users' stored ...