Proximity readers continuously transmit a low-level fixed radio frequency (RF) signal that provides energy to the card. When the card is held at a certain distance from the reader, the RF signal is absorbed by a small coil inside the card that powers up the card’s microchip which contains a unique identification code. Once powered, the card transmits the code to the reader. The whole process is completed in microseconds. The big advantage of proximity over other technologies lies in its simplicity. There are no moving parts, no mechanical wear, no slots, and no read heads to maintain. The reader can be concealed inside walls or special enclosures and poses even fewer problems when surface-mounted because it has no opening with which to jam or tamper. The proximity card is extremely secure and practically impossible to duplicate. Proximity cards are less prone to physical damage or loss, saving you money in reduced card replacement costs. Read ranges depend primarily on the reader. The larger the read range, the larger the reader’s concealed antenna and, hence, the size of the reader.
Access control panels (also known as “Access Controllers”) are installed in each building where access control is to be provided. Card readers, electric lock hardware, and other access control devices are all connected to the access control field panels. The access control panels are used to process access control activity at the building level. The number of access control panels to be provided in each building depends on the number of doors to be controlled. Access control panels are usually installed in telephone, electrical, or communications closets.
Access control keypads are devices which may be used in addition to or in place of card readers. The access control keypad has numeric keys which look similar to the keys on a touch-tone telephone. The access control keypad requires that a person desiring to gain access enter a correct numeric code. When access control keypads are used in addition to card readers, both a valid card and the correct code must be presented before entry is allowed. Where access control keypads are used in place of card readers, only a correct code is required to gain entry.
While traditional access control systems might prompt a user to provide a proximity card or a smart card to gain access to a protected resource, a biometric security system requires the user to present their fingerprint (or other biometric) to the system, which is then matched against a stored image to verify the user’s identity. Biometric access control systems tie a unique physical attribute of a user to the data that allows access. The most common biometric access systems use fingerprints, but these systems can also use iris and retinal scans, hand geometry, and facial recognition technology.