Do you think that keys and locks are the oldest man-made security tool? Forget it. Guardhouses go back hundreds, if not thousands of years as a place a person would sit or stand, observe, control access, alert others and take occasional action such as dumping hot oil over the wall. These permanent and temporary structures, built in or brought in, are used in most every country.
The events of September 11, 2001 changed the way business thought about perimeter security and access control. Rather than just a barrier to keep intruders out, fences and gates are installed with protection against potential terrorist attacks in mind.
