A smart card is a credit card-sized, tamper-resistant security device
that offers functions for secure information storage and information
processing that rely on VLSI chip technology. A smart card actually
contains a secure microprocessor chip embedded in the card. The chip
can implement a secure file system, compute cryptographic functions,
and actively detect invalid access attempts. With proper application of
file system access rights, a smart card can be safely used by multiple,
independent applications.
A smart card is distinguished from a magnetic stripe card (e.g.,
typical U.S. credit card) in that a magnetic stripe card has no VLSI
circuitry, and thus no active security procedures and no built-in
tamper-resistance. Anyone with an appropriate card reader can read
whatever is on the card. The current cost for magnetic stripe cards
(March 1994) is around $.50-$1.00 per card in quantities of 1000.
Smart cards are also distinguished from ``SuperSmart'' or ``token'' cards. These use a small LCD to display the time of day encrypted using an internal key that is programmed at the time of manufacture. Such cards have no storage capabilities and no interface to external computer systems. They perform a single, well-defined function that can be used in authentication protocols: users manually type the digits displayed on the card (which are updated periodically) as part of authenticating to a host. These cards are not capable of performing more extensive functions as part of a security system, and thus are not evolutionary. Cost (as of March 1994) for ``SuperSmart'' cards is on the order of $60/card in quantities of 250-500 (based on a cost of $20 per year, and battery lifetime of around 3 years).