Black Box Explains...Electronic access control.
When you have something valuable—your network servers, for instance—you want to limit access. But traditional mechanical locks and keys have severe limitations when you want to limit or control access to a large space shared by many users. It’s a matter of degree: A locked server cabinet with two keys in the hands of two IT members is not a problem; a locked server room with many keys in the hands of a large IT staff is a problem. When many people have keys, problems arise because keys can be lost, stolen, or duplicated. It becomes easy to lose track of who has keys and, if there’s a security problem, you have no idea who had access, and you may have to re-key the locks and replace all the keys.
Electronic access control solves the problems associated with traditional mechanical keys through the use of electronic locks in which each user has a unique electronic key. Electronic access enables you to control who is allowed into your building, who can get into each area within your building, and which times access is allowed. It even enables you to track when and where each user enters.
How access control works.
For electronic access control, an electronic credential is provided to each user. This can be a magnetic card, a personal identification number (PIN) to enter onto a keypad, or even a biometric scan. The user presents this credential to a reader to be granted entry. However, the reader doesn’t make the decision about whether to grant entry; this decision is made by a device called a door controller. A door controller contains the programming to manage all aspects of an entryway and may manage as many as eight readers. It receives information from the reader, makes the decision to open the entryway, and activates the lock relay controlling the entryway. It may also record all entries in real time, which can later be downloaded to a PC for archiving and reporting. Door controllers are frequently linked to a central system so all entryways can be monitored from one location.
Electronic access control primarily uses one of three different kinds of electronic credentials: proximity (close-range or long-range), keypad, or biometric.
The close-range proximity electronic credential is an electronically encoded card or tag that is swiped through a card reader or simply presented near a reader to gain entry. Close proximity credentials are by far the most popular kind used for access control but can be vulnerable to illegal entry by a person who’s found or stolen a card.
Long-range proximity electronic credentials are also available. These systems usually have ranges of a few feet rather than the mere inches of a close-range system. Although they can be valuable for parking areas or handicapped entrances, these long-range systems tend to have the problem of being inadvertantly tripped by a passerby with a credential.
A keypad credential requires a user to type a PIN into a keypad before granting access. These systems are generally regarded as less secure because users may “lend” their codes to another person but cannot prevent further use unless the code is changed. It can also be relatively easy to learn a code through watching.
The most sophisticated type of credential is the biometric in which a user presents a body part to be scanned before being granted entry. The most common kinds of biometrics in use today are iris scans and thumbprint scans, although some systems also use other distinct identifying characteristics such as facial appearance, hand geometry, handwriting, retinal pattern, vein pattern, or voice.
There was a time when biometrics had a reputation for being slow and unreliable. However, the technology has improved dramatically in recent years and—unlike proximity credentials and PINs—biometrics are almost impossible to borrow or counterfeit, making this one of today’s most reliable choices.
For areas where security requirements are very stringent, it’s not uncommon to require two different electronic credentials (for instance, a magnetic swipe card along with a PIN).
The advantage of tracking.
A major advantage of electronic access control is the authority it gives you. Not only does it enable you to decide exactly who is allowed to go where and when, but it also documents and reports access activity. If you have a security incident, you can quickly learn who had access to critical areas before and after the incident.
Electronic access control is a perfect complement to video surveillance and alarm systems in a comprehensive security plan.
Who uses electronic access control?
• Secure server rooms use it to prevent sabotage or vandalism.
• Hotels use it by providing electronic room keys that can also open doors to pool and spa areas.
• Hospitals use it to keep unauthorized personnel from seeing private records and to secure sensitive areas such as pharmacies and surgical floors.
• Day care centers use it to ensure that no strangers have access to their charges.
• Parking areas use it to prevent car theft and carjackings.