Monday, December 20, 2010
Inside of Smart card
A smart card, chip card, or integrated circuit card (ICC), is any pocket-sized card with embedded integrated circuits. There are two broad categories of ICCs. Memory cards contain only non-volatile memory storage components, and perhaps dedicated security logic. Microprocessor cards contain volatile memory and microprocessor components. The card is made of plastic, generally polyvinyl chloride, but sometimes acrylonitrile butadiene styrene or polycarbonate . Smart cards may also provide strong security authentication for single sign-on within large organizations. A smart card may have the following generic characteristics:
Dimensions similar to those of a credit card. ID-1 of the ISO/IEC 7810 standard defines cards as nominally 85.60 by 53.98 millimetres (3.370 × 2.125 in). Another popular size is ID-000 which is nominally 25 by 15 millimetres (0.984 × 0.591 in) (commonly used in SIM cards). Both are 0.76 millimetres (0.030 in) thick.
Contains a tamper-resistant security system (for example a secure cryptoprocessor and a secure file system) and provides security services (e.g., protects in-memory information).
Managed by an administration system which securely interchanges information and configuration settings with the card, controlling card blacklisting and application-data updates.
Communicates with external services via card-reading devices, such as ticket readers, ATMs, etc.
Contact smart card
Illustration of smart card structure and packaging
Contact smart cards have a contact area of approximately 1 square centimetre (0.16 sq in), comprising several gold-plated contact pads. These pads provide electrical connectivity when inserted into a reader.
The ISO/IEC 7810 and ISO/IEC 7816 series of standards define:
physical shape and characteristics
electrical connector positions and shapes
communications protocols, including commands sent to and responses from the card
Cards do not contain batteries; power is supplied by the card reader.
A smart card pinout
Power supply input.
Reset signal, used to reset the card's communications.
Provides the card with a clock signal, from which data communications timing is derived.
Ground (reference voltage).
Programming voltage input - originally an input for a higher voltage to program persistent memory (e.g., EEPROM), but now deprecated.
Serial input and output (half-duplex).
The two remaining contacts are AUX1 and AUX2 respectively, and used for USB interfaces and other uses.
Contact smart card readers are used as a communications medium between the smart card and a host (e.g., a computer, a point of sale terminal) or a mobile telephone.
Because the chips in financial cards are the same as those used in Subscriber Identity Modules (SIMs) in mobile phones, programmed differently and embedded in a different piece of PVC, chip manufacturers are building to the more demanding GSM/3G standards. So, for example, although the EMV standard allows a chip card to draw 50 mA from its terminal, cards are normally well below the telephone industry's 6 mA limit. This allows smaller and cheaper financial card terminals.