This is a electronic system that can control the flow of personnel through a designated area of even the control of personnel or vehicles in to a particular area.
These system can work in many ways:-
1) By a Personal Identification Number (PIN) in to a key pad.
2) By a personal card.
3) By a proximity tag
4) By a BIO scan of a piece of your body.
5) By any multiple of the above.
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