Hardware Reference
In-Depth Information
Biometric Devices
Biometric devices
identify users by scanning for one or more physical traits. Some common
types include fi ngerprint recognition, facial recognition, and retina scanning.
Law enforcement agencies have been using
fi ngerprint recognition
for over 100 years, and
no two prints have yet been found to be identical, even in genetically identical twins. That's
because fi ngerprints develop in the womb, and they aren't preprogrammed at conception.
More recently, computerized fi ngerprint scanners have taken the place of manual ink prints,
and the technology for reading fi ngerprints has become so affordable that it's built into
many computer systems, including consumer-level notebook PCs.
Some fi ngerprint scanners use a rapid laser to detect the ridges in a person's fi ngers;
others have an electrostatically sensitive pad that detects the current formed by the small
quantities of water in a fi ngerprint.
Facial recognition
software works in conjunction with a camera (like the webcams built
into some notebook computers) to scan the face of the person who is logging in. The facial
scan is matched with existing previous scans of that same person stored on the computer.
Some consumer-level notebook PCs now come with an option of logging into the OS via
facial recognition as an alternative to typing a login password.
Data and Usage Permission
Next we'll look at security measures that allow authorized users to view certain data or use
certain applications while preventing unauthorized users from doing so.
Controlling Screen Visibility
Unauthorized people can gain access to confi dential information not only by actively stealing
the data, but by viewing the screen casually, as a passer-by or as a nonchalant snoop in an
adjacent workstation.
One way to prevent others from looking at your screen while you're away from your
desk is to set up a screensaver, as you did in Exercise 9.1. The screen becomes obscured
after a certain period of inactivity. Not all the screensaver choices provide the same level
of screen-hiding, so choose a screensaver with an eye toward fi nding one that provides as
much privacy as possible.
To prevent others from looking at your screen as you're working, you might consider
orienting your monitor in such a way that it's diffi cult for others to read. For example, you
can sit with your back to a wall or window, with the monitor's back side facing out.
If it's impossible to hide the monitor from unauthorized lookers adequately, and if the
data on the screen is highly confi dential, you may fi nd a screen fi lter useful. A
screen fi lter
(also called a
privacy screen
) directs the light from the display at a restricted angle so that
anyone who isn't viewing it straight on won't be able to read it clearly.
