User Guide

Internet Security and Privacy
62 Internet Guard Dog
Javacontainsaninternalsecuritysystemthataddressessecurityrisks.ActiveX
usesadifferent model,based oncertificateauthentication.Certificatescontain
information a bout who developed the A ctiveX code. The idea here is that if
you know who developed the code, it is safe to run it. Both security schemes
offer a level of safety, but no one can yet promise that executable content is
entirely safe.
Nasty applets
One possible security threat is a malign Java or Active X program that attacks
your computer over the Web. A nasty applet might, for example, thwart Java
security by circumventing its security model, and destroy data on your hard
disk, or grab sensitive information from your hard drive. The latest browsers
have done a good job of fixing these issues. Aslongas you are using the latest
version of y our browser, you are protected. To date, there have been no
legitimate reports of hostile Java orActiveX harming anyone. However, there
is no guarantee that an attack will not happen in the future.
Can I prevent programs from accessing the Internet?
You can use Guard Dog to specify the applications that are allowed to access
the Internetfrom your computer. Obviously, your default Internet browser is
one of these applications.
IftheGuard DogGatekeeper is runningin thebackgroundwhileyouwork on
the Internet, each time an application tries to access t he Internet a dialog box
appears to ask if you want to allow this access once only, always, or never.
Computer viruses and the Web
A computer virus is a small computer program that automatically replicates
itself and spreads from one computer to another. Viruses may infect
programs, your hard drive, and even some document files that employ
macros. Viruses do not infect data files, but they can create problems that
prevent you from accessing your data. V iruses are not accidents—they are
always created by computer programmers.
PC viruses are similar to biological viruses in that they:
• Are spread from host to host—the “host,” in this instance, is your PC.
• Are very good at reproducing themselves.
• Can wreak havoc on an infected host system.