Intrusion Detection (Definition)

Intrusion detection can be defined as any form of activity that is designed to identify an unauthorized compromise taking place inside or from outside that is targeted towards a resource only restricted to certain authorized personnel. Intrusion is a crime and can be subjected to penalties once detected.

The Physical Aspect of Intrusion Detection

The physical aspect of intrusion detection is to detect an intruder by various means such as monitoring and surveillance of facilities via Closed Circuit Cameras and other devices such as biometric devices. It has served more as a preventive measure for intruders and they have been found more useful in forensics and investigation of an unwanted incident (Wetzel, 2014).

Physical Security

Physical security is a practice design to deny access to the resources to an unauthorized individuals. Physical security can be as simple as a locked door or as sophisticated as giant barriers.

The general objectives of physical security are

  • Keep the facility clear from intruders.
  • Security system must be able to distinguish between authorize and unauthorized personnel.
  • Prevent, irritate or at least delay an intruder.
  • Detect, monitor and record intrusion activities where intruders cannot easily be distinguished from customers or public such as in banks.
  • Trigger intrusion alerts such as alarms or sirens (, 2014).

Devices for Physical Security

There have been many Physical security devices that are designed to fight physical security threats in different ways. Some of the most famous devices are as follows.

Closed Circuit Cameras (CCTV cameras)

CCTV camera are Cameras in which the circuit is closed and connected with the television unlike the direct circuit cameras that has an open circuit to catch signals in the form of air waves, infrared waves, micro waves, and others. CCTV cameras have very wide spread applications and some of them fall outside the realm of security. Some security applications of CCTV cameras are to monitor the inside of a bank and help in controlling vandalism inside buses, trains and other public services. The CCTV cameras can be immensely useful tools when connected with the Internet and any personal and public place can be monitored from virtually anywhere in the world. It is also possible to record the videos of these CCTV cameras utilizing Digital Video Recorders (DVRs) for many years in some cases. Some CCTV cameras also come with certain features such as motion detection and email alerts. Network Attached Storage or built in flash memory for a complete standalone operation are also enhanced features that make the security surveillance more feasible and effective

Biometric Systems

Biometrics Systems allow the achievement of quantifiable data that is bound to human body in any certain way that can be acquired for identification, authentication and authorization.

The biometric devices can obtain data from DNA, ears, eyes, figures or palms, voice, odor even gate to produce output that can justify and establish the identity of a person that is physically accessing a facility or functioning inside the a restricted area (, 2014).

Recently there are some breakthroughs in medical science that may lead to the utilizations of signals from the human brain and heart for identification of a person. It has been observed that every individual has a unique brain and heart signature. Once the technology is perfected it will be more foolproof to serve in the arsenal of security devices.



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