INTRODUCTION:
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The 'exterior' refers to the area directly outside of a building and the things
within the building which are on the exterior. These obviously are: doors, air
conditioning ducts, windows, walls, roofs, garages, etc. I don't believe the
word 'exterior' is the exact definition of what this article will encompass,
unlike the 'perimeter', but it's the best I could come up with. This article
primarily is of an informative nature, although methods of "attacking,
defeating, and bypassing" will be explained. Its purpose is not specifically to
encourage you to breach a facility's security, although I acknowledge that it
could be used as such. Some of the devices mentioned in the physical security
series are used in homes as well as corporate, industrial, and military
installations, but my aim is specifically towards the commercial aspect of
buildings, not homes and apartments. Entering a facility to obtain information
such as passwords or manuals is one thing, breaking into someones' home to
steal their personal belongings is another.
THE EXTERIOR:
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A facility's second line of defense against intrusion is its' exterior. The
exterior may have any or all of the following:
* Window breakage detectors
* Keypad systems
* Card access control systems
* Magnetic locks and contacts
* Security lighting and CCTV
CCTV which is also used, was mentioned in Part I: The Perimeter.
Card Access Control devices will be mentioned in Part III: The Interior.
WINDOWS:
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Windows are a large security hole for buildings. You may notice that many phone
company buildings and data processing centers have few if any windows. There
are two things that can be done to secure windows aside from making sure they
are locked. One is to make them very difficult to break, and the other is to
detect a break when and if it occurs. Here is a quick breakdown of the common
types of glass/windows in use today:
Plate glass: Can be cut with a glass cutter.
Tempered: Normally can't be cut. Breaks up into little pieces when broken.
Safety: You need a hatchet to break this stuff.
Wire: This has wire criss-crossed inside of the glass, making it very hard to
break, and even harder to actually go through the opening it is in place of.
Plexy: Very hard to break, doesn't really shatter, but can be melted with the
use of a torch.
Lexan: This is used in bulletproof glass. One of the strongest and most secure
types of glass.
Herculite: Similar to Lexan.
Foil tape:
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This is by far the most common, and probably the most improperly installed form
of glass breakage detection, which also makes it the most insecure. This is
usually a silver foil tape about 5/16" wide which should be placed on the whole
perimeter of a glass window or door. In the case of plexyglass or a similar
material, the tape should be placed in rows separated by 6-12 inches.
The older foil was covered with a coating of eurathane or epoxy which enabled
it to stick onto the glass. The newer foil has an adhesive back making
installation much easier. There should be two connectors which are located at
the upper top part of a window, and the lower part of the window which connects
the foil to the processor, thus, completing the circuit. Foil may or may not
have a supervised loop. If it is supervised, and you use a key to scratch the
foil (when it is turned off) making a complete break in it, an alarm will sound
when it is turned on.
Foil is commonly used as a visual deterrent. Many times, it will not even be
activated. The easiest way to determine if the facility is trying to 'B.S.' you
into thinking they have a security system, is to see if there are any breaks
in the foil. If there is a clean break, the 6-12V DC current which is normally
making a loop isn't. Thus, breaking the glass will do nothing other than make
some noise unless you take steps against that happening.
As was stated, foil is the most improperly installed type of glass breakage
detection. When it is installed improperly, it will not cover all the area it
should. An easy way to defeat this is by the following diagram:
+-------------+
! ........... !
! . . ! . = foil tape
! . put . ! - = top/bottom of door
! . contact . ! ! = sides of door
! . paper . ! / = dividing line between 2 pieces of contact paper
! . in . ! $ = ideal places for initial breakage
! . this +-! ' = clear area or outline of second piece of contact paper
! . area ! ! <-- door handle
! . +-!
! . . !
! ........... !
!/////////////!
!'''''''''''''!
!' '!
!$'''''''''''$!
+-------------+
As you can see, the installer neglected to place the foil all the way down to
the bottom of the glass door. There is enough room for a person to climb
through. They may have thought that if someone broke the glass, it would all
break, which is normally correct. But if you obtain some strong contact paper,
preferably clear, adhere it to the glass as shown, and break the bottom part at
the '$' it will break up to the '/' line and thats it. Thus, leaving the foil
in-tact. This will work on tempered glass the best, and will not work on Lexan
or Plexyglass. There is a transparent window film with a break strength of up
to 100 pounds per square inch which can be obtained from Madico, Inc. It is
called, Protekt LCL-400 XSR, and makes glass harder to break and stays
essentially in place even when broken. This can be used in place of the contact
paper. Obviously, it is also used to protect glass from breakage.