About Smart Cards : Frequently Asked Questions
Smart Card FAQ
- What is a smart card?
- What are the ISO/IEC 14443 and ISO/IEC 7816 standards?
- What is a contactless smart card?
- How do contactless smart cards work?
- What is contactless payment?
- How do smart cards help to protect privacy?
- Why are smart cards better than other ID token technologies?
- How can smart cards be used to help assure privacy in a biometrics-based system?
- What is an RFID tag?
- Is contactless smart card technology the same as RFID technology?
- What security capabilities do contactless smart cards support?
A smart card is a device that includes an embedded integrated circuit that can be either a secure microcontroller or equivalent intelligence with internal memory or a memory chip alone. The card connects to a reader with direct physical contact or with a remote contactless radio frequency interface. With an embedded microcontroller, smart cards have the unique ability to store large amounts of data, carry out their own on-card functions (e.g., encryption and mutual authentication) and interact intelligently with a smart card reader. Smart card technology conforms to international standards (ISO/IEC 7816 and ISO/IEC 14443) and is available in a variety of form factors, including plastic cards, key fobs, watches, subscriber identification modules used in GSM mobile phones, and USB-based tokens.
For the purposes of this FAQ, “card” is used as the generic term to describe any device in which smart card technology is used.
ISO/IEC 14443 is the international standard for contactless smart chips and cards that operate (i.e., can be read from or written to) at a distance of less than 10 centimeters (4 inches). This standard operates at 13.56 MHz and includes specifications for the physical characteristics, radio frequency power and signal interface, initialization and anticollision protocols and transmission protocol.
ISO/IEC 7816 is the international standard for contact smart cards. ISO/IEC 7816 Parts 4 and above are used by both contact and contactless smart card applications for security operations and commands for interchange.
A contactless smart card includes an embedded smart card secure microcontroller or equivalent intelligence, internal memory and a small antenna and communicates with a reader through a contactless radio frequency (RF) interface. Contactless smart card technology is used in applications that need to protect personal information and/or deliver fast, secure transactions, such as transit fare payment cards, government and corporate identification cards, documents such as electronic passports and visas, and financial payment cards. Example applications using contactless smart card technology include:
The U.S. FIPS 201 Personal Identity Verification (PIV) card being issued by all Federal agencies for employees and contractors;
The Transportation Worker Identification Credential (TWIC) being issued by the Transportation Security Administration;
The First Responder Authentication Card (FRAC) being issued in Department of Homeland Security pilots;
The new U.S. ePassport being issued by the Department of State;
Contactless payment cards and devices being issued by American Express, MasterCard and Visa;
Contactless transit fare payment systems currently operating or being installed in such cities as Washington, DC, Chicago, Boston, Atlanta, San Francisco and Los Angeles.
Contactless smart cards have the ability to securely manage, store and provide access to data on the card, perform on-card functions (e.g., encryption and mutual authentication) and interact intelligently with a contactless smart card reader. Contactless smart card technology and applications conform to international standards (ISO/IEC 14443 and ISO/IEC 7816). Contactless smart card technology is available in a variety of forms - in plastic cards, watches, key fobs, documents and other handheld devices (e.g., built into mobile phones).
Contactless smart card systems are closely related to contact smart card systems. Like contact smart card systems, information is stored on a chip embedded within the contactless smart card. However, unlike the contact smart card, the power supplied to the card as well as the data exchanged between the card and the reader are achieved without the use of contacts, using magnetic or electromagnetic fields to both power the card as well as to exchange data with the reader.
The contactless smart card contains an antenna embedded within the plastic body of the card (or within a key fob, watch or other document). When the card is brought into the electromagnetic field of the reader, the chip in the card is powered on. Once the chip is powered on, a wireless communication protocol is initiated and established between the card and the reader for data transfer.
The following four functions describe at a high level the sequence of events that happen when a contactless smart card is brought near a card reader:
- Energy transfer to the card for powering the integrated circuit (chip)
- Clock signal transfer
- Data transfer to the contactless smart card
- Data transfer from the contactless smart card
Hence, once the card is brought within range of an electromagnetic field of the required frequency, the card will be powered up, ready to communicate with the reader. Since the contactless smart cards described in this FAQ are based on the ISO/IEC 14443 standard, this frequency is 13.56 MHz and a reader that complies with the standard would have an activation field (range) of about 4 inches (approximately 10 centimeters). In other words, the card needs to be within 10 centimeters of a reader for it to be effectively powered; however, the effective range for communications for the card to be read will depend on a number of factors like the power of the reader, the antenna of the reader and the antenna of the card.
Contactless payment is a change to the way debit or credit payment is handled when making a purchase. Contactless payment transactions require little to no physical connection between the card and the checkout device. Instead of “swiping” or “inserting” a card, the contactless card or fob is tapped on or held within an inch of a machine that reads the card, with the payment information is sent to the merchant wirelessly. Contactless credit and debit cards include a smart card chip.
In the U.S., contactless credit or debit cards or small keychain devices are being issued by a number of financial issuers (American Express, Chase, MBNA, Citibank, HSBC Bank, Keybank, Wells Fargo, Citizens Bank). For additional information on contactless payment, see the Smart Card Alliance Contactless Payments Resources.
Smart cards offer a number of features that can be used to provide or enhance privacy protection in systems. The following is a brief description of some of these features and how they can be used to protect privacy.
Authentication. Smart cards provide mechanisms for authenticating others who want to gain access to the card. These mechanisms can be used to authenticate users, devices, or applications wishing to use the data on the card’s chip. These features can be utilized by a system to protect privacy by, for example, ensuring that a banking application has been authenticated as having the appropriate access rights before accessing financial data or functions on the card.
Secure data storage. Smart cards provide a means of securely storing data on the card. This data can only be accessed through the smart card operating system by those with proper access rights. This feature can be utilized by a system to enhance privacy by, for example, storing personal user data on the card rather than in a central database. In this example, the user has better knowledge and control of when and by whom their personal data is being granted access.
Encryption. Smart cards provide a robust set of encryption capabilities including key generation, secure key storage, hashing, and digital signing. These capabilities can be used by a system to protect privacy in a number of ways. For example, a smart card system can produce a digital signature for the content in an email, providing a means to validate the email authenticity. This protects the email message from subsequently being tampered with and provides the email recipient with an assurance of where it originated. The fact that the signing key originated from a smart card adds credibility to the origin and intent of the signer.
Strong device security. Smart card technology is extremely difficult to duplicate or forge and has built-in tamper-resistance. Smart card chips include a variety of hardware and software capabilities that detect and react to tampering attempts and help counter possible attacks. For example, the chips are manufactured with features such as extra metal layers, sensors to detect thermal and UV light attacks, and additional software and hardware circuitry to thwart differential power analysis.
Secure communications. Smart cards provide a means of secure communications between the card and card readers. Similar in concept to security protocols used in many networks, this feature allows smart cards to send and receive data in a secure and private manner. This capability can be used by a system to enhance privacy by ensuring that data sent to and from the card is not intercepted or tapped into.
Biometrics. Smart cards provide mechanisms to securely store biometric templates and perform biometric matching functions. These features can be used to improve privacy in systems that utilize biometrics. For example, storing fingerprint templates on a smart card rather than in a central database can be an effective way of increasing privacy in a single sign-on system that uses fingerprint biometrics as the single sign-on credential.
Personal device. A smart card is, of course, a personal and portable device associated with a particular cardholder. The smart card plastic is often personalized, providing an even stronger binding to the cardholder. These features, while somewhat obvious, can be leveraged by systems to improve privacy. For example, a healthcare application might elect to store drug prescription information on the card instead of in paper form to improve the accuracy and privacy of a patient’s prescriptions.
Certifications. Many of today’s smart cards have been certified that they comply with industry and government security standards. They obtain these certifications only after completing rigorous testing and evaluation criteria by independent certification facilities. These certifications help systems protect privacy by ensuring that the security and privacy features and functions of the smart card hardware and software operate as specified and intended.
Smart cards are widely acknowledged as one of the most secure and reliable forms of an electronic identification (ID) token. A smart card includes an embedded integrated circuit chip that can be either a microcontroller chip with internal memory or a secured memory chip alone. The card communicates with a reader either through direct physical contact or with a remote contactless electromagnetic field that energizes the chip and transfers data between the card and the reader. With an embedded microcontroller, smart cards have the unique ability to store large amounts of data, carry out their own on-card functions (e.g., data storage and management, encryption, decryption, and digital signature calculations) and interact intelligently with a smart card reader.
A smart card ID can combine several ID technologies, including the embedded chip, visual security markings, magnetic stripe, barcode and/or an optical stripe. By combining these various technologies into a smart card ID token, the resulting ID can support both future and legacy physical and logical access applications. They can also support other applications that have traditionally required separate ID processes and tokens.
Biometrics are used in many new identity management systems to improve the accuracy of identifying individuals. How can smart cards be used to help assure privacy in a biometrics-based system?
Smart cards provide a highly effective mechanism to protect the privacy of an individual that has a requirement to use a biometric identity system.
The biometric information can be stored on the smart card rather than in an online database, allowing the biometric owner the opportunity to manage the physical possession of the card holding the individual’s biometric information.
The biometric data can be secured with state-of-the-art encryption techniques while providing full three-factor authentication capability at the card/reader level.
- Something you have – the card with all of its security capabilities
- Something you know – a password or personal identification number (PIN)
- Something you are – the biometric
In a non-smart-card-based application, the password or PIN and biometric would be stored in an online database outside the control of the individual and the biometric information would be captured and passed to an application for matching.
- The individual’s biometric can be captured by a reader and passed to the smart card for matching, rather than passing the stored biometric information to the reader for matching. The individual’s biometric information would never leave the card, preventing virtually any possibility of compromise.
Radio frequency identification (RFID) tags are used in a wide range of applications such as: identifying animals, tracking goods through the supply chain, tracking assets such as gas bottles and beer kegs, and controlling access into buildings. RFID tags include a chip that typically stores a static number (an ID) and an antenna that enables the chip to transmit the stored number to a reader. Some RFID tags contain read/write memory to store dynamic data. When the tag comes within range of the appropriate RF reader, the tag is powered by the reader’s RF field and transmits its ID to the reader.
RFID tags are simple, low-cost and commonly disposable, although this is not always the case such as reusable laundry tags. There is little to no security on the RFID tag or during communication with the reader. Any reader using the appropriate RF frequency (low frequency: 125/134 KHz; high frequency: 13.56 MHz; and ultra-high frequency: 900MHz) and protocol can get the RFID tag to communicate its contents. (Note that this is not true of car keys which contain a secure RFID tag.) Passive RFID tags (i.e., those not containing a battery) can be read from distances of several inches (centimeters) to many yards (meters), depending on the frequency and strength of the RF field used with the particular tag. RFID tags have common characteristics, including:
Low cost designs and high volume manufacturing to minimize investment required in implementation.
Minimal security in many applications, with tags able to be read by any compatible reader. Some applications like car keys do have security features, most notably provisions to authenticate the RFID tag before enabling the ignition to start the car.
Minimal data storage comparable to bar code, usually a fixed format written once when the tag is manufactured, although read/write tags do exist.
Read range optimized to increase speed and utility.
No. There is significant confusion in discussions of RF-enabled applications, with contactless smart card technology often incorrectly categorized as ‘RFID.’ There are a wide range of RF technologies used for a variety of applications – each with different operational parameters, frequencies, read ranges and capabilities to support security and privacy features. For example, the RFID technologies that are used to add value in manufacturing, shipping and object-related tracking operate over long ranges (e.g., 25 feet), were designed for that purpose alone and have minimal built-in support for security and privacy. Contactless smart cards, on the other hand, use RF technology, but, by design, operate at a short range (less than 4 inches) and can support the equivalent security capabilities of a contact smart card chip.
Contactless smart cards use RF technology, but, by design, operate at a short range (less than 4 inches) and can support the equivalent security capabilities of a contact smart card chip (see below). Contactless smart cards and readers conform to international standards, ISO/IEC 14443 and ISO/IEC 7816, and can implement a variety of industry-standard cryptographic protocols (e.g., AES, 3DES, RSA, ECC).
The contactless smart chip includes a smart card secure microcontroller and internal memory and has unique attributes RFID tags lack – i.e., the ability to securely manage, store and provide access to data on the card, perform complex functions (for example, encryption and mutual authentication) and interact intelligently via RF with a contactless reader. Applications using contactless smart cards support many security features that ensure the integrity, confidentiality and privacy of information stored or transmitted, including the following:
Mutual authentication. For applications requiring secure card access, the contactless smart card-based device can verify that the reader is authentic and can prove its own authenticity to the reader before starting a secure transaction.
Strong information security. For applications requiring complete data protection, information stored on cards or documents using contactless smart card technology can be encrypted and communication between the contactless smart card-based device and the reader can be encrypted to prevent eavesdropping. Hashes and/or digital signatures can be used to ensure data integrity and to authenticate the card and the credentials it contains. Cryptographically strong random number generators can be used to enable dynamic cryptographic keys, preventing replay attacks.
Strong contactless device security. Like contact smart cards, contactless smart card technology is extremely difficult to duplicate or forge and has built-in tamper-resistance. Smart card chips include a variety of hardware and software capabilities that detect and react to tampering attempts and help counter possible attacks. For example, the chips are manufactured with features such as extra metal layers, sensors to detect thermal and UV light attacks, and additional software and hardware circuitry to thwart differential power analysis.
Authenticated and authorized information access. The contactless smart card’s ability to process information and react to its environment allows it to uniquely provide authenticated information access and protect the privacy of personal information. The contactless smart card can verify the authority of the information requestor and then allow access only to the information required. Access to stored information can also be further protected by a personal identification number (PIN) or biometric to protect privacy and counter unauthorized access.
Support for biometric authentication. For human identification systems that require the highest degree of security and privacy, smart cards can be implemented in combination with biometric technology. Biometrics are measurable physical characteristics or personal behavioral traits that can be used to recognize the identity or verify the claimed identity of an individual. Smart cards and biometrics are a natural fit to provide two- or multi-factor authentication. A smart card is the logical secure storage medium for biometric information. During the enrollment process, the biometric template can be stored on the smart card chip for later verification. Only the authorized user with a biometric matching the stored enrollment template receives access and privileges.
Strong support for information privacy. The use of smart card technology strengthens the ability of a system to protect individual privacy. Unlike other technologies, smart card-based devices can implement a personal firewall for an individual, releasing only the information required and only when it is required. The ability to support authenticated and authorized information access and the strong contactless device and data security make contactless smart cards excellent guardians of personal information and individual privacy.
It is important to note that information privacy and security must be designed into an application at the system level by the organization issuing the contactless device, card or document. It is critical that issuing organizations have the appropriate policies in place to support the security and privacy requirements of the application being deployed and then implement the appropriate technology that delivers those features. The ability of contactless smart card technology to support a wide array of security features provides organizations with the flexibility to implement the level of security that is commensurate with the risk expected in the application.