To understand the functioning of access control mechanism, let’s take an example of HID proximity cards. HID proximity cards are used for providing physical access control. These cards are fitted with robust physical access control mechanism. These cards are also known as access control cards and contains programming commands that are readable by the proximity card reader and governs and regulates the physical access. Each card comprises of an integrated circuit containing programming features. Proximity cards are not run by any battery or power source, rather they uses radio frequency signal which are transmitted by a transmitter. When the proximity card is in the area of proximity reader, the proximity card reader reads the programming data from the proximity card. And once the program is successfully implemented, physical access is granted.
