Access control concept is all around us. From the lock on your front door or car door to the Personal Identification Number (PIN) for your Automated Teller Machine (ATM) card, we encounter access control systems every day. access control is everywhere. Access Control Systems are designed to help ensure that only authorized or qualified people are allowed to enter an exclusive space.
Electronic Access Control Systems concept utilize a computer, credential, credential reader, and door lock to control access electronically. Elements at the door also include an alarm point to tell if the door has opened without authorization and a request-to-exit sensor to allow the door to unlock for those inside to exit without setting off an alarm. The access control portal is coupled with a wall or fence to prevent going around the portal.
Credentials: Access control systems rely on credentialed users. Credentials may be something you have, something you know, or something about you that is unique. Something you have might be an access card, something you know might be a keypad code, and something about you that is unique might be your fingerprint.
Credential Readers: The system combines the credential with a credential reader (card reader, keypad, or biometric reader) to send a code to the computer where it is compared to a database of codes. If a match is found, the computer orders the portal to unlock the door and allow your entry (accompanied by a green light on the credential reader). It also makes an entry into a data log to record the entry. If no match is found, it rejects your entry attempt (buzzer at the door accompanied by a red light on the credential reader) and it enters an entry into the log recording the improper attempt including the card number or improper keypad code.
Who, Where, and When: Electronic Access Control Systems focus on who, where, and when, and access is granted on a “Who, Where, and When” formula. Each authorized user (Who) is valid for given portals (Where) and on a certain authorized schedule (When) — who is allowed to enter, where can they enter, and when are they allowed to enter or exit. Historically, this was handled by keys and mechanical locks. Authorized users were given a key for each lock, and the keys were good at any time. This resulted in many keys and when a key was lost, the lock had to be re-keyed and all key holders had to be issued a new key. This was not practical for large facilities and did not provide for time-sensitive access control. With Electronic Access Control Systems, each user is given only one key (like an access card) and the Access Control System database records where and when the card is valid. If the user loses his card, the card is voided in the database and a new card is issued. No other cardholders are affected, and no locks must be re-keyed.
Two-Factor Authorization: Additional security can be ensured by using two-factor authorization. In this case, access to a critical area such as a server room or vault requires the presentation of two credentials in a short period of time, typically one from an employee and one from a manager. Another form of two-factor authorization is created by requiring the user to present two factors such as a card and a keycode, or a card and a biometric credential such as a fingerprint.
Employee and Visitor Access Control: Cards are typically issued to employees and worn on their clothes by means of a clip or lanyard. Access Control Systems in facilities that receive visitors can be set up with a special visitor card to allow for contractors, vendors, and visitors to have access to certain designated areas. Typically, the Visitor Access Control system operates as a subsystem of the Access Control System and works with either a temporary paper access card or with a conventional access card specially marked to show that the cardholder is a visitor.
Photo Identification: Most Electronic Access Control Systems utilize access cards that bear the photo and name of the cardholder. This aids in identification of users and helps ensure that the cardholder is indeed the valid user of that specific card.
Alarms: Most Access Control Systems concept incorporate an alarm monitoring element. This allows intrusion detection to the facility or zones within the facility. The Access Control System will also record the event into a log file. Many if not most Security Portals utilize an alarm sensor to detect if the portal has been forced open or left (propped) open. The software for a portal is intrinsically capable of managing the Security Portal alarm. Those alarms are also bypassed (ignored) automatically when the door is opened legally to enter or to exit.
Events: The concept of Events is central to the real power of advanced Alarm/Access Control Systems. An Event is an automatic action that can be taken by the system in response to a stimulus. Examples of events are as simple as unlocking a door in response to a valid card or as complex as turning on after-hours path lights from the parking garage to a worker’s office space while simultaneously starting up the air conditioning system for his office and warming up the coffee pot. Advanced systems allow for complex events that take multiple conditions and logic into consideration; for example, changing what a guard will see on a workstation in response to the time of day and the Department of Homeland Security threat level.
Video System Integration: In response to an alarm or an unauthorized access attempt (and many other kinds of events), the Alarm/Access Control System can cause the Security Video System to display one or more video cameras that are related to the event. This can help security staff to quickly assess the nature and seriousness of the security incident and to coordinate an appropriate response.
References :
- ELECTRONIC ACCESS CONTROL by Thomas Norman
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