Security has always been one of man's necessities. Right from our ancestors who used to

bar the entrance of their cave dwellings with logs or a large stone to the modern era of the

motion sensor detectors, man has constantly developed and modernized the methods used

to provide security for his possessions, especially for his home.

Perhaps the earliest way man had discovered to protect himself and his belongings

was the guard dog. Dogs have, since time immemorial, been man’s best friend. Highly

adaptive, possessing superior intelligence and extremely loyal, the canine have long

been entrusted with the charge of guarding his master’s property. The most prolific and

suitable security dog breeds are arguably the Rottweiler, the German Shepherd and the

Scottish Terrier. There are a few specific reasons for this. All these breeds are excitable

and will bark vigorously at the presence of an intruder or in most situations that they

think are out of the ordinary. Even today, dogs are a preferred method for security as they

provide companionship too.

Door locks are one of the primary components of any home or office. Having a good

lock ensures us varying degrees of security from intrusion. Degree of security depends

largely on the type and kind of locking system used. The most common kinds of lock

used is the deadbolt, the wedge and the knob lock. The deadbolt is the most favored one

as it provides the maximum degree of security. It has a distinct advantage over the spring-

bolt system in that the deadbolt is considerably heavier and cannot be forcibly pried or

`jimmied` by an intruder. Most deadbolts require the correct key, which moves the bolt to

the `open` position, opening the lock. A common variation is the vertical deadbolt, which

can be used for added security, as the vertical position of the lock prevents it from being

forced open by using a bar or another object between the lock and the doorframe.

Door phones have been popular and widespread in use in many offices, homes and

apartment buildings due to its simplicity of installation and versatility of use. The ability

to identify the person requesting access to your premises has always been a crucial

one. Door phones provide this facility employing intercom technology. Using this, a 2-

way conversation can be initiated, giving the concerned person the option to allow or

deny access. Door phones have evolved from voice models to video models which are

available in the market today. Video models allow the person inside to actually see the

person requesting access, and thus provide added security.

Perhaps the most serious non-human threat to a building or structure is damage incurred

due to fire. More so nowadays, as most buildings and apartments contain multiple

connections for electricity, gas and various other electrical connections. Any one of these

can be considered a hazard, if leakages or breakages occur. In case of such occurrences,

the best method to avoid loss of life or property is the installation of a smoke and fire

alarm system. The fire alarm system is basically classified into two categories – the

manual and the automatic versions. Manual devices work on the premise that the fire

has been discovered by an occupant of the building. The alarm can then be activated

by either pushing a button or pulling a lever, triggering an audio response, in effect

warning everyone in the premises. Automatically activated devices can take many forms

intended to respond to any number of detectable physical changes associated with fire:

convected thermal energy; heat detector, products of combustion; smoke detector, radiant

energy; flame detector, combustion gasses; carbon monoxide detector and release of

extinguishing agents; water-flow detector. The newest innovations can use cameras and

computer algorithms to analyze the visible effects of fire and movement in applications

inappropriate for or hostile to other detection methods.

One of the most widely used and popular methods of security today in the CCTV.

Abbreviated for Closed Circuit Television, CCTV has gained tremendous popularity

due to its capability for both real-time and recorded footages. Perhaps this is why it has

become a fixture in law enforcement agencies and security details around the world.

CCTVs all work on the basic principle of transmitting images and videos taken by

cameras or video recorders from the point of origin to a central monitoring area, normally

manned by security personnel.

The motion sensor detector is a tool used by security specialists around the world. It

involves a motion sensor that transforms the detection of motion into an electric signal.

This can be achieved by measuring optical or acoustical changes in the field of view.

There are various types of detectors including the Passive Infrared Sensor, which detects

emission of body heat to identify an intruder, Ultrasonic Sensors, which sends out pulses

and measures the reflection off a moving object and the Microwave Sensor, which sends

out microwave pulses and measures the reflection off a moving object.

Many offices and establishments have adopted the card entry system and the keypad

identification system to monitor entry into their premises.

Most cards used for passcard entry have a magnetic stripe on it. This stripe contains

information about the user and other data which is written with the help of an encoder. It

works on the principle of varying magnetic fields. A card reader can read the information

on the card using these fields present on the card, thus allowing or denying access to the

user.

The Keypad Identification System employs numeric or alphanumeric keypads that

require the user to enter a required sequence of characters, which is then compared to a

database and if matching, allows access to a particular area. The advantage of this system

is that the person holding the required sequence has to reveal the information in order to

gain access. In other words, no one can gain access without the prior knowledge of the

primary user.

The card entry system and the keypad identification systems are preferred methods

of security in an establishment, as they can be configured and designed to restrict and

manage access for a user for different levels. Thus, a person using a card or having a

keypad combination does not necessarily gain access to the entire facility. His passcard or

password can be preset to allow only certain areas.

The most popular and commonly used security measure designed for the home is the

Burglar Alarm System. This system employs most of the technologies described above,

with the added functionality to trigger a silent or non-silent response at the local or

a remote station. The principle used here is that the owner of the house activates the

alarm when going out, or while sleeping. A combination of motion sensors and door-

entry detectors detect any unauthorized intruders and set off the alarm. The alarm can be

custom-set to flash lights, produce loud sound or trigger an alarm at the nearest police

station. The burglar alarm system can easily be deactivated by using a passkey or a

passcode.