The perimeter protection and detection system is the foundation of any physical or logical protection measures. The purpose of the perimeter protection and detection system is to provide early warning of the attack, to detect entry attempts at the perimeter, to deter attacks, and if necessary to actively counter any of these attempts. Combination with a physical barrier in order to have a resilient security concept and to facilitate the usage of alternative access paths is an important part of a robust perimeter protection strategy.
To get started, one of the early steps is to categorize the perimeter (inside and outside) into different sectors. And then have defined measures in each of the sectors that enable a more structured approach to counter any threats. Here are four different sectors a perimeter area should be divided into and what security measures should be implemented in each of them:
The outermost layer of a multi-layered protection concept is always sector 0. As a rule, this comprises the entire surrounding field of a protected facility including any demarcation barriers (e.g., fences). Inside sector 0, it is possible to make unauthorized approaches to the perimeter more difficult and/or to detect them. Surveillance of this sector makes sense only if persons approaching the protected area (perimeter area) should be detected.
It is the most important sector because it is the first point of contact between a trespasser and the protected area. Sector 1 is a barrier that prevents access to the protected area. The barrier may consist of a fence, ditch, wall, or other construction with limited or no passage possibilities. The purpose of the protection target is to prevent and/or detect any trespassing in Sector 1. This sector can be divided into sub-sectors in order to facilitate surveillance and/or control measures (e.g. by using video cameras and/or alarms).
Sector 2 is the perimeter area. It excludes sector 3. It is usually considered to be more vulnerable than Sector 1 and 3 because it is easier for people to gain access to it from outside the perimeter. Surveillance of this sector makes sense if the purpose is to detect whether people are lingering in this sector without authorization. Another possible reason for surveillance of sector 2 would be to prevent theft of goods from a storage yard. Sector 2 may comprise a few subareas that must be treated separately, e.g. parking lots and/or open spaces in front of buildings with controlled access that should not be entered without prior authorization.
The automatic surveillance of sector 3 requires a higher technical and financial effort as compared to sectors 1 and 2. The reason for this is that persons who are located in sector 3 cannot be reliably detected by means of video surveillance due to the large distance, the short exposure time, obstructions, and other factors. The detection of persons in sector 3 may be possible by means of thermal imaging cameras in combination with the analysis of body heat radiation (body temperature). This technique is used in special cases only because it requires a lot of technical effort and is still subject to development.
The last few years have seen a noticeable increase in security consciousness. The tendency is towards requiring new defensive equipment with higher levels of security. Perimeter protection and detection systems are expensive, yes, but if your business cannot afford to be exposed at all times, you may have no choice but to deploy one of these or a similar solution. The most important thing is that it needs to be properly implemented by trained professionals.