ExpressPay
Newer American Express credit cards come with a feature known as ExpressPay. Similar to Mastercard's PayPass and JPMorgan Chase's Blink, ExpressPay is a method of contactless payment, different from the standard magnetic stripe that has become ubiquitous on credit and debit cards. ExpressPay is based on a family of technologies known as RFID, ISO 14443 with extensions specifically.
Embedded in the plastic of the card is a small microcontroller, along with a metal antenna. The microcontroller implements the authentication used by the card, which is a type of challenge-response system. The RFID chip is commonly embedded in various types of American Express Blue and Clear cards.
ExpressPay was also available in a key fob for holders of American Express cards, but American Express is discontinuing support for key fobs, and all existing fobs will be deactivated by July 31, 2008. [1] American Express does not appear to have any plans to stop issuing RFID enabled cards, however.
Similar key fob based systems may be available for holders of other major credit cards or debit cards.
So far, a few retailers have rolled out RFID readers that accept ExpressPay. They include Meijer, CVS/Pharmacy, Best Buy, Chevron Corporation, and some McDonald's locations. Office Depot has implemented Express Pay in all 1200 stores.[2]
