A new way to control your credit card

Carl Gunter

That's a very smart chip on the stored-value card in Carl Gunter's hand.

Photo by Daniel R. Burke

Carl Gunter, professor of computer and information science, has designs on your credit cards. He wants to turn them into smart cards. He’s already got one—a Barclays Bankcard with a tiny gold square on the front, no bigger than a thumbtack, which is a programmable computer chip.

Gunter and his colleagues are poised to exploit a collection of innovations that are coming out for payment cards. “We are particularly interested in something called the global platform. It is the idea of credit cards that can be [programmed] by multiple vendors. This is an idea that is quite new. It is a consortium that is trying to develop an interface for payment cards that allows you to download third party software onto the card.”

One simple use for this technology would be a payment card that doubles as a loyalty card. The card would keep track of your purchases from, for example, Starbucks and Barnes and Noble and reward you with discounts for being a return customer.

“Our application is a bit different,” Gunter continued. “Our idea is to use the little agents that live on the card to watch what you are doing and then saying it’s OK. You are stopped from doing something rather than rewarded. It uses the same underlying technology of the global platform to create, for example, a credit card for your teenager with a limit on purchases over $200, or a University of Pennsylvania purchase card that knows the date and can only be used on weekdays, or a card that knows the time and is restricted to business hours.

“The point is that the bank doesn’t have to create the policies, you or the institution that gives you the card can do that.”

The cards are cryptographically protected. “We are exploiting the idea that the card has a high degree of tamper resistance so that ordinary users would not have the equipment, knowledge or wherewithal to change the parameters you’ve set.”

The same technology could be used in cell phones that use a smart card. “You could give a phone to someone, but restrict it to local calls or designate which overseas area codes could be accessed,” he explained.

Gunter has a few other clever ideas he’s working on: a satellite tracking technology that will mediate how people will be able to contact you based on your location; a defense against denial of service attacks and a new form of e-mail based on business-to-business electronic commerce that would be much more secure and cut down on spam; and last but certainly not least for the average technology-challenged adult, a package with a computer program on it that would tell your microwave what to do with your Lean Cuisine.

Originally published on October 2, 2003