What is perimeter security’s importance?
Perimeter protection is the vital outer layer in a best-practice security model of: deter, detect, delay, and respond. It is where standoff begins and determines the amount of time that an organization will have for intervening in a security breach. Erecting fencing at a property’s outermost point, for example, allows for more opportunity to intercept an intruder than restricting valuable assets to a secured area inside a facility. Consequently, an organization must think strategically about how far out it can extend “detection” in a layered security approach.
What is the best strategic approach?
Adequate perimeter security is rarely achievable through deployment of a single security barrier or monitoring system, be it trained security officers, an intrusion detection system, or video surveillance. The best perimeter security strategy typically involves an “all of the above” approach that consists of layers of security before adversaries reach their target. Strengthening perimeter protection can increase the amount of time between detecting an intrusion and the point at which an attack would be successful, which layers of security help to facilitate.
What provides the foundation to robust perimeter security?
An effective layered security posture creates concentric rings of defense and incorporates several types of security measures, such as integrating physical protective measures (e.g., vehicle barriers, lighting, and electronic security systems) with procedural security measures (e.g., security officer incident response). However, many security layers, such as incident response, depends on initial detection of the event, which makes positioning of the outermost layer especially important.
What are key elements to keep in mind?
(a) Securing’ the restricted area and (b) Monitoring’ the restricted area. Securing the perimeter is physically limiting accessibility so there is a low likelihood of an adversary successfully breaching it (e.g., fencing, natural obstacles, security force, and so on). ‘Monitoring’ is the need for awareness of the perimeter, including immediately beyond the perimeter (the “buffer zone”) and the area just inside the perimeter. Frequently, effective monitoring is accomplished by using intrusion detection systems integrated with other electronic surveillance systems, and often in conjunction with a security force, to deter, detect, communicate, and evaluate the presence of unauthorized persons or vehicles or unauthorized activities.
How do we balance protection vs. cost?
Extending security to the outermost edge of a property is always the most robust security posture and improves the odds of thwarting an intrusion (by increasing the time for response). However, it is also more expensive to push security to the property boundary than securing a building or a select area inside a building and not always warranted considering the value of what is being protected and its likelihood of being targeted. For high-value targets like critical infrastructure, extending the security perimeter as far as possible is advisable, but other organizations may conclude that it requires too much investment. To determine if the outer ring of perimeter security is adequate at a given location, it may be instructive to model different attack scenarios (see below for an example). Such scenario planning can be a useful way to describe for decisionmakers how securing and monitoring a facility’s perimeter is necessary to successfully prevent an attack on a critical asset (including on staff and executives) inside a facility.
What if our resources are limited?
When extending the security perimeter is too costly or impossible, certain other measures can help, such as developing plans to quickly enhance security if it becomes necessary and increasing security visibility through use of perimeter patrols, uniformed officers, and security posts at entrance points.
Scenario planning example:
