A card key reader is a type of entry device that requires a key card to enter. The two main types of card key systems are magnetic card key readers and mechanical based card key readers. Both types are used to provide security to buildings and computer systems. Without a key card that is activated through a key card reader, the user will not be admitted.
A key card is a small, flat card approximately the size of a credit card that has a digital code embedded in it that when presented to the key card reader allows the person to enter. The most common types of key cards include a magnetic stripe, mechanical hole card, and smart cards. The magnetic stripe key card stores data just like a credit card and will provide the magnetic stripe card key reader with information such as the person's name and areas of the building the person can access.
The most common use of the magnetic stripe key card reader is in hotels where each room has a unique key card that will only open that room. The magnetic stripe on the key card is slid into a slot in the card key reader which reads, recognizes the room number and unlocks the door. This type of key card reader is also used to enter office buildings and other businesses by employees who have been issued key cards. Subways and other types of public transit systems may use prepaid magnetic stripe key cards that allow travelers to ride without the need to provide cash each time.
Mechanical hold key cards work more like a traditional key lock than a magnetic stripe card. Holes are punched out of the key in a specific sequence that matches a card key reader. When the key card is inserted into the card key reader, it physically moves a bolt so the door will unlock. The pattern of holes can be easily replicated, which may cause security concerns so this type of key card reader is no longer widely used.
Smart cards are the same size as the magnetic stripe key card but include embedded integrated circuits. This allows much more information to be stored in a credit card size device. Most often the smart cards are used at point of sale (POS) terminals or in conjunction with mobile phones but may also be used by businesses to record employee movements within a building. Smart card key card readers do not require the card to actually be swiped, because it can pick up information off any smart card in the vicinity using radio frequency (RF) technology. This makes it especially helpful if large numbers of people need to move through a particular area and would otherwise cause delays by having to individually swipe their key card.