A keycard lock is a

lock Lock(s) or Locked may refer to: Common meanings *Lock and key, a mechanical device used to secure items of importance *Lock (water navigation), a device for boats to transit between different levels of water, as in a canal Arts and entertainme ...

operated by a keycard, a flat, rectangular

plastic card Plastic cards usually serve as identity documents, thus providing authentication. In combination with other assets that complement the data stored on the card, like Personal identification number, PIN numbers, they also serve authorization purpose ...

. The card typically, but not always, has identical dimensions to that of a credit card, that is ID-1 format. The card stores a physical or digital pattern that the door mechanism accepts before disengaging the lock. There are several common types of keycards in use, including the mechanical holecard,

barcode A barcode or bar code is a method of representing data in a visual, Machine-readable data, machine-readable form. Initially, barcodes represented data by varying the widths, spacings and sizes of parallel lines. These barcodes, now commonly ref ...

, magnetic stripe, Wiegand wire embedded cards,

smart card A smart card (SC), chip card, or integrated circuit card (ICC or IC card), is a card used to control access to a resource. It is typically a plastic credit card-sized card with an Embedded system, embedded integrated circuit (IC) chip. Many smart ...

(embedded with a read/write electronic microchip),

RFID Radio-frequency identification (RFID) uses electromagnetic fields to automatically identify and track tags attached to objects. An RFID system consists of a tiny radio transponder called a tag, a radio receiver, and a transmitter. When tri ...

, and NFC proximity cards. Keycards are frequently used in

hotel A hotel is an establishment that provides paid lodging on a short-term basis. Facilities provided inside a hotel room may range from a modest-quality mattress in a small room to large suites with bigger, higher-quality beds, a dresser, a re ...

s as an alternative to mechanical keys. The first commercial use of key cards was to raise and lower the gate at automated parking lots where users paid a monthly fee.

Overview

Keycard systems operate by physically moving detainers in the locking mechanism with the insertion of the card, by shining LEDs through a pattern of holes in the card and detecting the result, by swiping or inserting a magnetic stripe card, or in the case of RFID or NFC cards, merely being brought into close proximity to a sensor. Keycards may also serve as ID cards, or as part of an NFC system, have the code transmitted to a

mobile phone A mobile phone or cell phone is a portable telephone that allows users to make and receive calls over a radio frequency link while moving within a designated telephone service area, unlike fixed-location phones ( landline phones). This rad ...

to be placed into a digital wallet system such as Apple Pay or Google Pay, negating the need for a physical keycard. Many electronic access control locks use a Wiegand interface to connect the card swipe mechanism to the rest of the electronic entry system. Newer keycard systems use

radio-frequency identification Radio-frequency identification (RFID) uses electromagnetic fields to automatically Automatic identification system, identify and Tracking system, track tags attached to objects. An RFID system consists of a tiny radio transponder called a tag, ...

(RFID) technology such as the TLJ infinity.

Types of card readers

Mechanical

Mechanical keycard locks employ detainers which must be arranged in pre-selected positions by the key before the bolt will move. This was a mechanical type of lock operated by a plastic key card with a pattern of holes. There were 32 positions for possible hole locations, giving approximately 4.3 billion different keys. The key could easily be changed for each new guest by inserting a new key template in the lock that matched the new key. In the early 1980s, the key card lock was electrified with LEDs that detected the holes. Magnetic stripe card - hotel key card

Wiegand cards

Since the keycode is permanently set into the card at manufacture by the positions of magnetic wires, Wiegand cards cannot be erased by magnetic fields or reprogrammed as magnetic stripe cards can. Many electronic access control locks use a Wiegand interface to connect the card swipe mechanism to the rest of the electronic entry system.

Magnetic stripe

Magnetic stripe (sometimes "strip") based keycard locks function by running the magnetic stripe over a sensor that reads the contents of the stripe. The stripe's contents are compared to those either stored locally in the lock or those of a central system. Some centralized systems operate using hardwired connections to central controllers while others use various frequencies of radio waves to communicate with the central controllers. Some have the feature of a mechanical (traditional key) bypass in case of loss of power.

Passive RFID

RFID cards contain a small chip and induction loop which the transmitter on the keycard reader can access. The main advantages with RFID cards is that they do not need to be removed from the wallet or pass holder - as the keycard reader can usually read them from a few inches away.

Access control

In the case of the hotel room lock, there is no central system; the keycard and the lock function in the same tradition as a standard key and lock. However, if the card readers communicate with a central system, it is the system that unlocks the door, not the card reader alone. This allows for more control over the locks; for example, a specific card may only work on certain days of the week or time of day. Which locks can be opened by a card can be changed at any time. Logs are often kept of which cards unlocked doors at what times.

Privacy

Computerized authentication systems, such as key cards, raise

privacy Privacy (, ) is the ability of an individual or group to seclude themselves or information about themselves, and thereby express themselves selectively. The domain of privacy partially overlaps with security, which can include the concepts of a ...

concerns, since they enable computer surveillance of each entry. RFID cards and key fobs are becoming increasingly popular due to their ease of use. Many modern households have installed digital locks that make use of key cards, in combination with biometric

fingerprint A fingerprint is an impression left by the friction ridges of a human finger. The recovery of partial fingerprints from a crime scene is an important method of forensic science. Moisture and grease on a finger result in fingerprints on surfa ...

and keypad PIN options. Offices have also slowly installed digital locks that integrate with key cards and biometric technology.

Gallery

File:HK Chai Wan Open Day 青年廣場 Youth Square Y-Loft 旅舍 Hotel room card.JPG, A hotel entry card used to enable a light switch File:OhanaKeycard.jpg, Illustrated instructions for use of mag stripe key card File:Rumsdörr, Rica Talk Hotel.jpg, Access control utilizing magnetic strip technology

References

{{DEFAULTSORT:Keycard Lock Locksmithing Locks (security device) Doors