The selection of reader and keypad combination affects the level of security at an entry point.
A keypad only installation is generally considered less secure than a reader only installation. The reasoning is that users may illegitimately “lend” their codes to another person but cannot prevent further use (in comparison to getting a card back) unless the code is changed. Moreover, a user’s code can sometimes easily be visualized and duplicated.
A reader only installation is the most common application but can be susceptible to illegal entry by a person who has found a card outside the protected site, such as in a parking lot or in public transport. Readers outside of a building may be more exposed.
Adding a keypad to a reader significantly increases the level of security. The user is now required to provide both a card and a keypad PIN code (Personal Identification Number). Optionally, the PIN code requirement can be scheduled for use only outside hours rather than during high traffic hours.
Long Range Proximity Readers
The most common uses for long range proximity readers are for parking entrances and per handicap facility requirements. Although several users request long range proximity, they are seldom informed of the actual “side effects” of these expansive readers. For an example, a long range reader installed at a door in a corridor may read the cards of any users walking by the door who do not have any intention of unlocking and entering that door. The door will actually unlock, and remain unlocked for a preset time, without the user’s knowledge. Here is another situation that happens frequently at a door: several users are outside the door having a discussion and finally, one user goes in. Chances are that the system may erroneously report the user having already entered. Therefore, make sure that readers are properly installed to prevent such instances and that a voluntary action from the user is necessary to unlock the door. In most cases, you may revert to a 10 cm (4 in) reading range! As far as parking lots are concerned, there are other alternatives with wireless fobs and vehicle tags