Entry-Control Approaches |
(Chapter 4 Entry-Control Technologies, Continued)
What you HAVE
In this approach, an ID card or badge is specially encoded to be recognized by a card reader. Validation of the card can be designed to electronically open a door lock, allow a turnstile to operate, or lift a mechanical arm that extends across a vehicle driveway. Viable card technologies for schools include bar codes or magnetic strips for card-swipe readers (such as those used for most credit cards) or passive or active radio frequency (RF) cards for proximity readers, which can validate a card several inches to several feet away (depending on the cost of the system). Card-swipe readers are probably more subject to vandalism as their read heads are fairly delicate. Proximity readers can be protected with a solid piece of plexiglass because actual contact of the card is not required. A proximity card reader might be an ideal entry control system for a teacher's parking lot, or for a computer lab. The newer smart cards are probably overkill for an entry control system.
- Strengths: No manpower is involved. These are mature technologies. Validation of a card can be turned off if the card is lost or stolen. When used in conjunction with a floor-to-ceiling turnstile, an authorized person cannot bring in unauthorized persons (exhibit 4.3). It is also possible to automatically update an attendance database when an ID card is read. These cards are generally tamperproof, and some have features that make them very difficult to counterfeit.
- Weaknesses: For an electronic lock or vehicle barrier, there is no way to ascertain that only a single authorized person is entering. Cards can be lent out. Cards can be used by others until the card is turned off by the school administration. Card-swipe readers can be subject to vandalism if in a vulnerable location. Card readers require a certain level of overhead to maintain, and regular updating of their databases is mandatory.
- Costs: Prices for the equipment to produce high-quality, tamperproof ID cards, with software to develop attractive customized designs, have come down greatly in just the past few years. A sophisticated printer that embeds the ink into the card cost as much as $25,000 just 4 years ago. Today, an entire system (a printer, a digital camera, and the software to operate them) that is more than adequate for most school's needs can be purchased for $6,000-$8,000. While every product is different, and there are many features that can be added that raise the price considerably, the supplies (inks, card blanks, and so forth) that a school must continually purchase to create cards readable by a card-swipe reader will cost the school about $1 per card. Supplies for cards readable by a proximity reader will run between $3 and $10 per card, depending on the capabilities of the system. Card-swipe readers and proximity readers cost between $150 and $300 per reader. The electronics, field panel, and computer system necessary to support a modest number of readers (typically, eight or fewer) will cost around $2,000-$3,000. Installation is usually a job most appropriate for an electrician.
Research Report: The Appropriate and Effective Use of Security Technologies in U.S. Schools