Readers and Keypads

Proximity

The fastest growing technology for access control applications, 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. A reader’s read range is always specified using standard cards. If the card’s coil is smaller, as in thin photo ID cards, keytag or keytag type cards, it may reduce the read range by up to 40%. There is a great variety of proximity readers designed for different environments including vandal resistant mullion mounts, smaller decor styles, and integrated keypad/reader units.

Biometrics

Biometric technologies include fingerprint, hand geometry, voice recognition, retinal scan, and any other method of identification based on unique personal characteristics. Biometric solutions consist of a reader that compares a user-selected template against the measured features of the actual person. Templates may be called up in a system manually by entering a PIN number or automatically by using bar code, magnetic stripe, smart card or proximity identification technologies.

Magnetic Stripe

The typical magnetic stripe card accommodates three tracks or areas for storing data. Banking and credit card operations rely on this technology, most frequently using Track 2 (sometimes referred to ABA-2 or ISO-2) to store their data. The card must be swiped or inserted into the reader so that the read head can pick up the card’s encoded data. This contact operation creates wear on both the card and the read head. With new high-density magnetic stripes, however, loss of data due to reasons other than physical damage is now uncommon. This technology provides a medium level of security because it is possible, with the right equipment and proper knowledge, to duplicate cards. Yet, lower cost for both readers and cards makes it an attractive choice for many users.

Bar Code

Bar code technology is very common in non-security applications but it is seldom the technology of choice for security. The card is swiped so that the cell inside the reader can read the bar code through a lens. Visible bar code technology has obvious security drawbacks. For example, cards can be duplicated with a photocopier or by faxing. Although it is possible to mask the bar code with a filter that makes duplication more difficult, most buyers prefer more secure technologies. The cards have an average life of 18 to 30 months. The reader lens requires cleaning once a year on average, or more if installed in dusty environments such as parking lots.

Wiegand

This technology was originally created to provide a permanently encoded card when magnetic stripe cards were too sensitive to magnetic fields. The Wiegand card contains a stream of “Wiegand effect” wire inside. As the card is swiped through an electromagnetic field inside the reader, the bits of wire create a data stream that is used to identify the user. Wiegand was the most common technology in high security applications before the advent of lower cost proximity technology.

Multiple Technology

Multiple technology cards are most often used on sites where a system, such as one that measures time and attendance, is already in place and uses magnetic stripe or bar code cards. If the customer wants higher security proximity cards for the access control system, the existing cards can be replaced by dual-technology cards which combine proximity and a second technology, such as bar code or magnetic stripe or even smart card. This is a more convenient alternative than asking employees to carry two cards. It is also less expensive and less time consuming than switching out all of the cards.