A card reader is a data

input device In computing, an input device is a piece of equipment used to provide data and control signals to an information processing system, such as a computer or information appliance. Examples of input devices include keyboards, computer mice, scanne ...

that reads data from a card-shaped

storage medium Data storage is the recording (storing) of information (data) in a storage medium. Handwriting, phonographic recording, magnetic tape, and optical discs are all examples of storage media. Biological molecules such as RNA and DNA are con ...

and provides the data to a computer. Card readers can acquire data from a card via a number of methods, including: optical scanning of printed text or barcodes or holes on

punched card A punched card (also punch card or punched-card) is a stiff paper-based medium used to store digital information via the presence or absence of holes in predefined positions. Developed over the 18th to 20th centuries, punched cards were widel ...

s, electrical signals from connections made or interrupted by a card's punched holes or embedded circuitry, or electronic devices that can read

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 ...

s embedded with either a

magnetic strip The term digital card can refer to a physical item, such as a memory card on a camera, or, increasingly since 2017, to the digital content hosted as a virtual card or cloud card, as a digital virtual representation of a physical card. They shar ...

, computer chip,

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 ...

chip, or another storage medium. Card readers are used for applications including

identification Identification or identify may refer to: *Identity document, any document used to verify a person's identity Arts, entertainment and media * ''Identify'' (album) by Got7, 2014 * "Identify" (song), by Natalie Imbruglia, 1999 * ''Identification ...

access control In physical security and information security, access control (AC) is the action of deciding whether a subject should be granted or denied access to an object (for example, a place or a resource). The act of ''accessing'' may mean consuming ...

and

banking A bank is a financial institution that accepts Deposit account, deposits from the public and creates a demand deposit while simultaneously making loans. Lending activities can be directly performed by the bank or indirectly through capital m ...

data storage Data storage is the recording (storing) of information (data) in a storage medium. Handwriting, phonographic recording, magnetic tape, and optical discs are all examples of storage media. Biological molecules such as RNA and DNA are con ...

, and

data processing Data processing is the collection and manipulation of digital data to produce meaningful information. Data processing is a form of ''information processing'', which is the modification (processing) of information in any manner detectable by an o ...

Mechanisms

Magnetic card readers

Magnetic stripe technology, usually called mag-stripe, is so named because of the stripe of magnetic oxide tape that is laminated on a card. There are three tracks of data on the magnetic stripe. Typically the data on each of the tracks follows a specific encoding standard, but it is possible to encode any format on any track. A mag-stripe card is cheap compared to other card technologies and is easy to program. The magnetic stripe holds more data than a barcode can in the same space. While a mag-stripe is more difficult to generate than a bar code, the technology for reading and encoding data on a mag-stripe is widespread and easy to acquire. Magnetic stripe technology is also susceptible to misreads, card wear, and data corruption. These cards are also susceptible to some forms of skimming where external devices are placed over the reader to intercept the data read.

Smart card readers

Smart card readers use an electrical current to read data from embedded circuitry or magnetic features in a card. A contact smart card must physically touch contacts on a reader to connect a circuit between them. A contactless smart card uses radio waves or a magnetic field to transmit information to a reader remotely (though most readers have a range of or less).

Contact smart card readers

A contact smart card reader is an electronic device that physically connects to an integrated circuit in a

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 ...

, supplies the circuit in the card with electricity, and uses

communications protocol A communication protocol is a system of rules that allows two or more entities of a communications system to transmit information via any variation of a physical quantity. The protocol defines the rules, syntax, semantics (computer science), sem ...

s to read data from the card. Smart card readers used for banking or identification may be connected to a keyboard to allow verification with a

personal identification number A personal identification number (PIN; sometimes RAS syndrome, redundantly a PIN code or PIN number) is a numeric (sometimes alpha-numeric) passcode used in the process of authenticating a user accessing a system. The PIN has been the key to faci ...

(PIN). If the card does not use any standard transmission protocol, but uses a custom/

proprietary {{Short pages monitor A card reader with a biometric system compares the

template Template may refer to: Tools * Die (manufacturing), used to cut or shape material * Mold, in a molding process * Stencil, a pattern or overlay used in graphic arts (drawing, painting, etc.) and sewing to replicate letters, shapes or designs C ...

stored in memory to the scan obtained during the process of identification. If there is a high enough degree of

probability Probability is a branch of mathematics and statistics concerning events and numerical descriptions of how likely they are to occur. The probability of an event is a number between 0 and 1; the larger the probability, the more likely an e ...

that the template in the memory is compatible with the live scan (the scan belongs to the authorized person), the ID number of that person is sent to a control panel. The control panel then checks the permission level of the user and determines whether access should be allowed. The communication between the reader and the control panel is usually transmitted using the industry standard

Wiegand interface The Wiegand interface is a de facto wiring standard which arose from the popularity of Wiegand effect card readers in the 1980s. It is commonly used to connect a card swipe mechanism to the rest of an access control system. The sensor in such a s ...

. The only exception is the intelligent biometric reader, which does not require any panels and directly controls all door hardware. Biometric templates may be stored in the memory of readers, limiting the number of users by the reader memory size (there are reader models that have been manufactured with a storage capacity of up to 50,000 templates). User templates may also be stored in the memory of the smart card, thereby removing all limits to the number of system users (finger-only identification is not possible with this technology), or a central

server Server may refer to: Computing *Server (computing), a computer program or a device that provides requested information for other programs or devices, called clients. Role * Waiting staff, those who work at a restaurant or a bar attending custome ...

PC can act as the template host. For systems where a central server is employed, known as "server-based verification", readers first read the biometric data of the user and then forward it to the main computer for processing. Server-based systems support a large number of users but are dependent on the reliability of the central server, as well as communication lines. 1-to-1 and 1-to-many are the two possible modes of operation of a biometric reader: * In the 1-to-1 mode a user must first either present an ID card or enter a PIN. The reader then looks up the template of the corresponding user in the database and compares it with the live scan. The 1-to-1 method is considered more secure and is generally faster as the reader needs to perform only one comparison. Most 1-to-1 biometric readers are "dual-technology" readers: they either have a built-in proximity, smart card or keypad reader, or they have an input for connecting an external card reader. * In the 1-to-many mode a user presents biometric data such as a fingerprint or retina scan and the reader then compares the live scan to all the templates stored in the memory. This method is preferred by most end-users, because it eliminates the need to carry ID cards or use PINs. On the other hand, this method is slower, because the reader may have to perform thousands of comparison operations until it finds the match. An important technical characteristic of a 1-to-many reader is the number of comparisons that can be performed in one second, which is considered the maximum time that users can wait at a door without noticing a delay. Currently most 1-to-many readers are capable of performing 2,000–3,000 matching operations per second.

Banking

Some banks have issued hand-held smartcard readers to their customers to support different electronic payment applications: *

Chip Authentication Program image:Barclays pinsentry.jpg, 250px, A Gemalto EZIO CAP device with Barclays PINsentry styling The Chip Authentication Program (CAP) is a MasterCard initiative and technical specification for using EMV banking smartcards for authentication, authent ...

(CAP) uses

EMV EMV is a payment method based on a technical standard for smart card, smart payment cards and for payment terminals and automated teller machines which can accept them. EMV stands for "Europay International, Europay, Mastercard, and Visa Inc., ...

banking cards to authenticate online transactions as a

phishing Phishing is a form of social engineering and a scam where attackers deceive people into revealing sensitive information or installing malware such as viruses, worms, adware, or ransomware. Phishing attacks have become increasingly sophisticate ...

countermeasure. *

Geldkarte GeldKarte () was a stored-value card used as an electronic cash system in Germany from 1996 to 2024. It operated as an offline smart card for small payments at installations like vending machines and to pay for public transport or parking ticke ...

is a German electronic purse scheme where card readers are used to allow the card holder to verify the amount of money stored on the card and the details of the last few transactions.

Data tabulation

Throughout the 20th century, punched card readers were used to tabulate and process data including census data, financial data, and government contracts. Punched card voting was widely used in the United States from 1965 until it was effectively banned by the

Help America Vote Act The Help America Vote Act of 2002 ( Pub. L.Tooltip Public Law (United States)107–252 (text) (PDF)), or HAVA, is a United States federal law, which was authored by Christopher Dodd, and passed in the House 357-48 and 92–2 in the Senate and was ...

of 2002.

References

{{DEFAULTSORT:Card Reader Computer storage devices Smart cards Solid-state computer storage media USB