Access control systems wide range of credentials can be used to replace mechanical keys. The electronic access control system grants access based on the credential presented. When access is granted, the door is unlocked for a predetermined time and the transaction is recorded. When access is refused, the door remains locked and the attempted access is recorded. access control singapore also monitors the door and warns you if the door is forced to open or stays open for too long after the door is unlocked.
When the badge is presented to the reader, the reader sends the badge information (usually a number) to a reliable processor, the control panel. The control panel compares the credential number to the access control list, permits or denies the submitted request, and sends the transaction log to the database. If access is denied based on the access control list, the door remains locked. If the credentials and access control list match, the control panel operates the relay and the relay unlocks the door. The control panel also ignores the door open signal to prevent alarms. Often the reader provides feedback, such as a flashing red LED for an access denied and a flashing green LED for an access granted.
The above description illustrates a single factor transaction. Credentials can be passed around, thus subverting the access control list. For example, Alice has access rights to the server room, but Bob does not. Alice either gives Bob her credential, or Bob takes it; he now has access to the server room. To prevent this, two factor authentication can be used. In a two-element transaction, the provided credentials and the second element are required to grant access. Another factor could be a PIN, second credential, operator intervention, or biometric input. Read more…
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