Physical Classifications of SmartCards

SmartCards are essentially working computers with an infinite possiblity of uses. On the physical level, SmartCards are classified as contact, contact-less, or as combinations of the two. Contact SmartCards require a reader (and/or writer) in which the card is inserted when it''s needed. Contact-less cards contain an antenna that may be read by remote receivers. Combination cards may be used both ways, depending on the applications it''s intended for.

For e-commerce purposes, you''ll likely find contact cards as the most prevalent, especially as the newer desktop computer systems, which come equipped with readers/writers either built-in to the keyboard or the computer chassis, become ubiquitous. An example of an external SmartCard reader from Gemplus Corporation is shown below.

Contact-less cards are most often found where transaction speed is critical, as with mass-transit toll payment and replenishment and physical access controls. These cards are similar to transponder units that have a variety of other uses where metered applications are present.