Lesson 6: Access Control

The least an organization should expect from an installed (entrance control) system is that it keep out unauthorized personnel but let in authorized users. Stephen M. Rogers

The goal of all human beings since we came together in social groups has been to feel secure and safe in our personal and group environment. Starting out with spears, rocks, and bramble-bush fences, we have developed much more sophisticated devices to protect our belongings and ourselves. Although considerable different in the use of modern technology, the same basic principles and techniques are used today. Ranging from electronic warning devices to nuclear weapons, the basic means of protection have remained using the same physical security concepts and principles to keep the "bad guys" out of our personal and collective space.

The use of physical security is based on what is sometimes referred to as the five Ds, which outline the primary purpose of each physical device or other security measure used. The five Ds are as follows:

• Deter: The very presence of physical security methods can often deter an intruder. The sight of a strong, high, well posted fence that protects the perimeter may just be enough to deter the intruder from attempting entry. Poorly built and poorly maintained fencing, gates, lighting, or other security systems send a message to the potential intruder that no one really cares about security at that facility.

• Detect: This is done by diverting the intruders and channeling them into areas where they can be seen (visual detection) or where they will activate alarms or monitors that will pinpoint their location (remote detection). It is crucial to provide for detection as soon as or, better yet, before the intruder has breached the perimeter of the facility.

• Delay: Even after the intruder decides to attempt entry and once inside the perimeter, the way barriers are planned and arranged can cause enough delay for special devices or security alert force to respond and thwart penetration, or effect capture as soon as possible after penetration. Making the scaling of a wall more difficult by angled overhead barriers, topping a fence with razor wire, or creating a series of barriers between the perimeter and the next area can slow the intruder down and make apprehension or retreat more likely.

• Deny: This is a major objective of any security, to deny the intruder access to the specific assets being secured. Denying the intruder is generally accomplished by a greater "hardening" of security nearer to the assets location. Either by making the barriers much more difficult closer to the asset or by providing a series of barriers that will allow the backup security force to arrive in time to apprehend the subjects.

• Destroy: Though not always the objective of security methods, in some cases, the last possible response may require the destruction of the intruder, or the destruction of the asset (i.e., a file on a computer that would compromise national security, or some deadly substance in a research laboratory). Destructive force, against (i.e., armed terrorists) may also be required as a response to protect the lives of personnel. Another meaning of destruction is the complete frustrating of the planned criminal activity by physical security means.

The need for security begins at the boundary of personal or community space. If that space is not clearly defined, or some method of definition and security warning is not provided at that point, the task of the invader of that space is made easy. In the interpersonal world of one-on-one human interaction, a simple step back or raised hand can define the borders of one’s personal space. Nations and states have clear border points, usually defined by some natural boundary (i.e., an ocean, river, or mountain range). But smaller pieces of personal property or commercial "turf" are often more difficult to delineate. This is where the role of physical security and the purposes of difficult types of such security, helps not only define the boundaries of the enterprise but also provide security and access control.

One way to look at security is from a line-of-protection viewpoint. The line from entry point to the asset is interdicted by a series of physical barriers that seem to be like the layers of an onion or the circles of a target, with the asset as the bull’s eye. Each layer has a specific way to provide physical security for the protection of the heart of the onion, the asset being protected. The line-of-protection layers are as follows:

• The outer perimeter is most generally defined as the point at which the controlling entity has ownership of or responsibility for the property, physical assets, and personnel within that boundary.

• Not all facilities have the luxury of a fenced and protected outer perimeter. The perimeter of many facilities might begin at the exterior of a building or building complex. Those who provide security planning through architectural design sometimes call this kind of first line of defense the building envelope. In planning for security on a building exterior, the security professional must consider at all times that this is a three-dimensional object that must be protected from the sides, top, and below.

• If the building interior security has been planned properly, the various parts of the activity will be divided into functional areas that have been designated by their level of risk and vulnerability.

• As one gets down to this final stage, there is a number of ways to harden the target. The specific room that houses the asset can be specially constructed for maximum security (as in a bank vault), or it can employ a number of physical security devices to ensure that it is especially difficult to penetrate the inner circle.

The use of alarms, either independently or in conjunction with other forms of monitoring, is an important adjunct to a good physical security plan. Alarms must have three basic components:

1. a triggering device

2. an enunciator that alerts some kind of recognition of penetration, and

3. a response of some kind.

It is clear that no alarm is effective as anything but an irritant to an intruder unless there can be some response by guards of others. Alarms can be used to frighten away an intruder if it is loud and perhaps includes a spoken message. Some alarms are silent but do alert a guard force or some other deterrent device to act to capture or destroy an intruder.

One of the major problems with alarm systems is that they tend to have a high ratio of false alarms. This crisis creates a number of problems, either with the local police (if they are tied into the system) or with the security response force. It has been reported that as many as 90% of alarms are found to be false, which results in negative attitudes to alarm systems.