Nowadays, Plastic ID cards are being used extensively for identification and authentication purposes in various applications such as driving licenses, Bank ATM card, Credit card, Club membership card, and in various Academic and commercial organizations as well. Some of these cards contain a magnetic-strip to make it machine readable. However these cards are not secure enough and given the right kind of equipment, the information on these cards can be modified easily.

Smart card is the youngest and cleverest one in the family of identification card. Its characteristic feature is in an integrated circuit chip(ICC) embedded in the card, which has components for the transmission, storage and processing of data. With the help of the ICC the smart cards have the ability to store data and carry out many on-card functions such as encryption and authentication in a secure manner. Smart card offers many advantages compared to magnetic-strip card. One of the important advantages is that stored data can be protected against unauthorized access and modification.

Smart cards can be divided into two groups according to the underlying technology.

• memory cards
• microprocessor cards

In memory cards data required for the application are stored in non-volatile memory typically implemented in EEPROM. Access to the memory is controlled by the security logic.

The microprocessor cards have a processor, which is surrounded by additional functional blocks such as ROM, EEPROM, RAM and I/O port. The ROM contains the chip's operating system. The EEPROM is the chip's non volatile memory. The I/O is for data transfer. It has an operating system especially designed for smartcards with the ability to process data inside the card itself and also carry small programs for local execution. The security features built into smart card chips are very sophisticated and if used properly can give ultimate security to the cards. Data residing in the chip is protected against external inspection or alteration with the help of secret keys of the cryptographic systems.

Smart cards can be categorized into the following based on the communication interface.

• contact smartcards
• contact-less smartcards
• dual interface or hybrid smartcards

Contact cards provide a landing terminal connector to which card gets connected to the interface device.

Contact less cards only need to be close enough to be in the range of the reader. Both the card and the reader have antennae and these communicate through radio frequencies. The cards derive their power also from the readers through conatct pins in case of contact cards and through RF in case of contactless cards.

The dual interface or hybrid cards provide both contact and contactless interfaces. these cards have contact interface and also antenna for communication. The specifications for smartcards are defined by ISO 7816 standards. The ISO 7816 standards are internationally accepted standards for smartcards. The different aspects of a smartcard such as: communication characteristics, physical properties etc. are defined in these standards.