Security has to be compared to related concepts: Safety, continuity,
reliability. The key difference between security and reliability is that
security must take into account the actions of people attempting to cause
destruction.
Security as a national condition was defined in a United Nations study
(1986)[citation needed], so that they can develop and progress freely.
With respect to classified matter, the condition that prevents unauthorized
persons from having access to official information that is safeguarded in the
interests of national security.
Measures taken by a military unit, an activity or installation to protect itself
against all acts designed to, or which may,
Perceived security compared to real security
Perception of security is sometimes poorly mapped to measureable objective
security. The perceived effectiveness of security measures is sometimes
different from the actually security provided by those measures. The presence of
security protections may even be taken for security itself. For example, two
computer security programs could be interfering with each other and even
cancelling each other's effect, while the owner believes s/he is getting double
the protection.
Security theater is a critical term for deployment of measures primarily aimed
at raising subjective security in a population without a genuine or commensurate
concern for the effects of that measure on—and possibly decreasing—objective
security. For example, some consider the screening of airline passengers based
on static databases to have been Security Theater and Computer Assisted
Passenger Prescreening System to have created a decrease in objective security.
Perception of security can also increase objective security when it affects or
deters malicious behavior, as with visual signs of security protections, such as
video surveillance, alarm systems in a home, or an anti-theft system in a car
such as a LoJack, signs.
Since some intruders will decide not to attempt to break into such areas or
vehicles, there can actually be less damage to windows in addition to protection
of valuable objects inside. Without such advertisement, a car-thief might, for
example, approach a car, break the window, and then flee in response to an alarm
being triggered. Either way, perhaps the car itself and the objects inside
aren't stolen, but with perceived security even the windows of the car have a
lower chance of being damaged, increasing the financial security of its owner(s).
However, the non-profit, security research group, ISECOM, has determined that
such signs may actually increase the violence, daring, and desperation of an
intruder [1] This claim shows that perceived security works mostly on the
provider and is not security at all [2].
It is important, however, for signs advertising security not to give clues as to
how to subvert that security, for example in the case where a home burglar might
be more likely to break into a certain home if he or she is able to learn
beforehand which company makes its security system.