McAfee Guard Dog, User Manual, Page: 72 / 89

Internet Security and Privacy
62 McAfee Guard Dog
Privacy on the Web
Who is snooping?
Hackers are a breed of human being that thrive on gaining illegal access to
computers in order to access, steal, and sometimes corrupt data. Many hackers
are quite benign: Breaking into a secure system is a challenge and a thrill. But
some computer hackers think that if they don’t care for someone or some
organization, it is OK to break in to their computers and wreak havoc. Others
hackers think that the on-line theft of money and resources is legitimate, as
long as it goes to support more hacking.
Snooping and sniffing
Since its inception, the Internet has been (and largely remains) an open
network. Openness means that information on the Internet travels without
any special security: Anyone who can monitor network traffic can intercept it.
This sort of monitoring is called “sniffing,” and is easy to perform using
“sniffers.” Sniffers are programs (or hardware devices) designed to monitor
data traveling over a network. Originally, sniffers were designed to help
network administrators track down networking problems. Unfortunately, the
same tool can also be used to steal information. Sniffers are insidious and
difficult to detect.
Sniffing often begins when a hacker breaches the security of a local Internet
Security Provider (ISP). A hacker does not need physical access to the ISP’s
premises—sometimes a telephone line is sufficient (although it is also possible
to sniff with physical access to network cables). Once a hacker compromises
an ISP’s system, the network traffic that travels through the ISP is no longer
secure.
Web servers and firewalls
Secure transactions are only one part of the problem. When an ISP’s Web
server receives information, the ISP must be able to keep the information safe.
Hackers like to attack the security of Web servers because Web server security
is still in its infancy. As a consequence, Web administrators assume that a Web
server is open to attack, and try to keep them decoupled from other,
mission-critical computers. Some Web applications must, however, interact
with corporate databases, an open door to a clever hacker. One form of
security technology called a “firewall” can close the door, but firewalls are
often maintained poorly, and even in the best environment, cannot safeguard
certain services.