Intrusion detection systems

Abstract

Intrusion detection systems (IDSs) are designed to detect the entry of unauthorized persons into a protected area. The IDS should alert the response force when there is a breach of the perimeter. Building walls and the perimeter protect and delay the entry of attackers for a time. Openings-doors, windows, vents, and some walls-are the weak points in a security system. Intruders, even highly skilled intruders, look for the easiest way into a facility. A facilities security system should protect the assets until response forces can arrive. The earlier the notice, the more time for the response force to arrive and contain the situation. An effective IDS will complement your overall security plan. Countermeasures should reduce risk to an acceptable level at an acceptable cost. From one perspective, the earlier the warning, the less you have to depend on the perimeter and access control systems to protect your assets, but your thinking is generally focused on how to secure the most for less. The basic components of an IDS are a sensor, an annunciator or alarm, and a transmission method from the sensor to the alarm. The response force completes the system. An alarm does no good if no one responds. This chapter will explore commonly available systems and discuss the uses of each system. Response forces are covered in Chapter 14.