− Ken Sakamura −
The cash cards and credit cards being used today are called magnetic stripe cards. A magnetic stripe similar to that found on audio or video cassettes is affixed to the card, onto which data is recorded as magnetic information. While these cards are inexpensive, costing only thirty or forty yen, their recording capacity is limited to several tens of characters.
IC cards feature an integrated circuit, or IC, instead of a magnetic stripe on the cards, and while the cost is higher at several hundred yen or more, they have a minimum recording capacity of several thousand characters. It is also possible to embed a microprocessor (and memory) into IC cards, thereby enabling the card itself to carry out program processing. The resultant cards are termed smart cards.
Apart from cash cards and credit cards, magnetic stripe cards are used across wide-ranging applications, such as telephone cards, pachinko (Japanese pinball machines), railway cards and other prepaid cards, as well as EFTPOS cards in shopping districts. However, counterfeiting and unauthorized used of these cards are occurring increasingly with defectiveness of security mechanism (illegal use prevent system), and it is becoming impossible to ignore the resultant economic losses. The following benefits can be achieved by using IC cards or smart cards instead of magnetic stripe cards.
- The storage capacity is at least 100 times greater than that of magnetic stripe cards.
- Counterfeiting and unauthorized use are more difficult than magnetic stripe cards.
- Information can be closed into the IC.
- Information can be encrypted.
- More expensive than magnetic stripe cards, but crime can be controlled.
In Europe, a leader in the adoption of IC cards, they are used widely as telephone cards, bank cards and credit cards, but they have yet to become popular on a large scale in Japan or the United States.
Magnetic stripe cards transfer and receive information by detecting and changing the direction of magnetization on the magnetic stripe by a device called a magnetic stripe card reader/writer. In contrast, IC cards transfer and receive information by inserting the card into a device called an IC card reader/writer that has an electrical terminal that sends and receives electrical signals with the IC. It is highly likely that inserting and withdrawing cards from these electrical terminals may result in contact defects. This type of card is referred to as a contact IC card. Distinct from this type of card is the contactless IC card which exchanges information between the IC card and the IC card reader/writer without contact by electromagnetic induction, light or radio waves. Using these cards it is sufficient to hold up the IC card to the reader/writer it is not necessary to insert the card, and there is no concern about contact defects.
Contactless IC cards can be classified as shown in Table 1 according to the distances from the reader/writer.
Frequencies and applications change according to the distance. Contactless IC cards can also be classified into those requiring and those not requiring batteries, but currently the majority of cards are battery-less type which have energy supplied wirelessly and do not encompass the bother of changing batteries. Inductive coupling is widely used for the transfer of power and information, but capacitive coupling is also used in close coupling applications. Microwave-type cards emit radio waves themselves, and require batteries. Contactless IC cards which are not card-shaped are often referred to as RF-ID (Radio Frequency Identification), and these are used in applications ranging from product management in factories to management of livestock. Generally Contactless IC cards and RF-ID are referred to as data carriers, and they are used in many fields where they are attached to objects to achieve a correspondence between the name and information concerning that object. In the Digital Museum, these are used as electronic tags to enable computers to discriminate between exhibits. Doing so has enabled the museum to manage exhibits efficiently, and has created many possibilities such as showing exhibits effectively to meet the needs of visitors.
Table 1 /TD> Distance Standard Frequency Applications Close coupling Within a few mm ISO/IEC 10536 4.91MHz Settlement, poor environments Remote coupling /TD> /TD> /TD> /TD> Proximity A few mm to several tens of cm ISO/IEC 14443 13.56MHz Railway tickets, ID cards Vicinity A few cm to 1 m ISO/IEC 15693 13.56MHz FA, distribution Microwave-type Several tens of cm to a few m Undefined 2.45GHz FA, distribution
