Cards with a magnetic stripe


Magnetic stripe is the oldest and the cheapest element enabling the transport of information that can be read automatically in card readers. Magnetic cards (ISO 7811) are commonly used to build systems using large numbers of cards where the existing technical infrastructure designed for reading magnetic stripes is the main criterion in choosing the data carrier. In practice, the majority of retail outlets and service points are in the possession of magnetic stripe readers. From the perspective of information security, the major disadvantage of such cards is lack of possibility of proper security of data stored on the magnetic stripe that can be easily copied.


In systems that use magnetic cards, all key information should be contained in the computer systems and the card should only carry the identification number. At present, HICO (high coercivity) type cards that have higher resistance to demagnetisation are applied most often. Such card has a high coercivity coefficient of the stripe (about 4000 oersteds) and the recording takes place on three tracks: the first track allows for recording 75 alphanumerical symbols, 40 symbols in the second track and 107 symbols in the third track. There are also LOCO (low coercivity) type cards, on the market. A LOCO card also has three tracks; however, its low coercivity (approximately 350 oersteds) makes the card very susceptible to demagnetisation.


Magnetic stripe cards are the most common type of cards appearing particularly in payment systems and loyalty programmes.