TABLE OF CONTENTS The popular media would have you believe that the cause of most network security problems is the hacker. However, if you ask people actually working in the field, they will tell you that nearly half the security breaches they encounter come from sources internal to an organization, and, in particular, employees. This means that it won t be sufficient to secure a network against external intrusion attempts; you must pay as much attention to what is occurring within your organization as you do to external threats.
The Internet has been both a blessing and a curse to those who rely on computer networks to keep an organization in business. The global network has made it possible for potential customers, customers, and employees to reach an organization through its Web site. But with this new access have come the enormous problems caused by individuals and groups attempting illegal entry into computer networks and the computer systems they support.
External threats are initiated by people known in the hacking community as crackers. Initially, the term hacker referred to someone who could write an ingenious bit of software. In fact, the phrase a good hack meant a particularly clever piece of programming. Outside of the hacking community, however, anyone who attempts illegal access to a computer network is called a hacker.
Hacking often involves becoming intimate with the details of existing software to give the hacker the...
