Clip and save online
Certifiably yours
Screen and screen again
Clip and save online
By Bruce Schechter
Coupons are an alluring sales tool. The promise of a bargain is enough to cause all but the most spendthrift to jam their pockets and drawers with scraps of paper. Businesses operating in the paperless world of e-commerce would like to issue coupons, too—but without a physical certificate, it's difficult to prevent counterfeiting and other scams. Recently, IBM Research teams invented "e-coupon" technology that solves those problems, while making possible new forms of targeting and promotion that would be impossible in the brick-and-mortar world.
The e-coupon technology was developed by teams at IBM's Thomas J. Watson Research Center's Institute for Advanced Commerce and at the India Research Laboratory. In one version of the system, an e-business can define a coupon and issue it to targeted customers. These store coupons sit in individual shopper wallets maintained in the storefront until shoppers redeem them. The merchant can choose from a wide variety of promotion methods. The store coupon system has been designed to work with IBM's Websphere commerce suite products. The hmv.com Web site runs an implementation by IBM Global Services.
In another version of the technology, called the manufacturer coupon, a manufacturer wishing to issue an electronic coupon goes to a "coupon mint" and generates e-coupons—small XML documents that contain encrypted information detailing the terms of the offer. The manufacturer then distributes the e-coupons to customers, who store them in an electronic wallet on their computer's hard drive or at a central server. Most of the time, manufacturers want to limit the use of the coupons to the customers to whom they were issued. Coupons can therefore be personalized with information such as customer's name or credit card number, which is verified at the time of purchase.
To redeem the coupon, a customer uploads it from the online merchant. The merchant sends the coupon to the coupon mint, which checks that it is valid and records that it has been used. This eliminates the problem of forgery and prevents merchants from reusing coupons. After validating the coupon, the mint issues the retailer a certificate of use that it can redeem with the manufacturer.
The e-coupon system makes possible new kinds of promotions undreamed of in the clip-and-save days. "Early bird" specials, for example, might be valid for the first 100 users. Or, to encourage people to use them quickly, coupons could slowly lose value as they age. The Indian researchers have even drawn inspiration from Las Vegas: coupons with randomly fluctuating values could add a bit of excitement to purchasing a bottle of shampoo.
Bruce Schechter, a freelance writer who lives in Brooklyn, is the author of My Brain Is Open: The Mathematical Journeys of Paul Erdös.
Certifiably yours
by Rowan Dordick
Trust is important in most human interactions, but is absolutely critical in the realm of e-business, according to Amir Herzberg, manager of e-business and security technologies at IBM's Haifa Research Laboratory.
Because one rarely knows with whom one is dealing, trust must be established not by a gut feeling but by secure mechanisms designed to ensure the businessworthiness of both parties. Haifa researchers have devised a scheme known as TrustEstablishment that accomplishes this in a simple and flexible manner.
Issues of trust come to the fore whenever a person requests access to a restricted service or Web site. An e-commerce site, for example, may offer discounts to a select group, perhaps employees of certain companies. One way to control access to the site or to identify who is entitled to a discount is to have the user present credentials, such as a digital certificate issued by one of the companies or a third party. The certificate allows the server to verify that the user is an employee, which it can do by checking that the user's browser contains the private key corresponding to the public key signed by the certificate issuer. Such certificates are bound to become more common, according to Yosi Mass, the leader of the TrustEstablishment project. "As new e-business models develop, such as electronic marketplaces that constantly add new member companies and customers, the need for a dependable trust mechanism will only increase," he says.
The trouble is, current schemes for controlling access to Web sites or e-businesses will grow cumbersome as users multiply. "Users," says Herzberg, "will have to acquire and keep track of a large number of certificates from organizations willing to vouch for them, while online businesses will need to interact with a huge number of approved certificate issuers in order to be able to process the certificates."
To avoid these bottlenecks in the growth of e-business—which are unavoidable in a hierarchical system based on authorized certificate issuers— TrustEstablishment promises to create a network of mutual trust in a bottom- up fashion. The idea is to extend the current model for access control so that trust can be established even when a business does not directly know anything about the issuer of a certificate.
Say that a hospital wants to restrict its online resources to physicians who are accredited in a particular specialty. One way to do that is to require that a physician bring a certificate from some other hospital. "But a given hospital is unlikely to know about every other hospital in the world," says Herzberg. "Our approach enables more powerful, flexible policies that do not require listing all the hospitals or, more generally, all the certificate issuers."
TrustEstablishment makes this possible by allowing certificates to be issued not only by hospitals to physicians but by one hospital to another. Then a hospital might state: "Bring certificates from two hospitals that we recognize, and then we will trust you." If the hospitals willing to issue a certificate to the physician are not on the list of recognized hospitals, they can obtain certificates from other hospitals until a link is established with two hospitals on the list. In this way, the number of known hospitals can continually grow through an expanding "web of trust," and does not depend on a fixed list of authorized hospitals.
To ensure that certificates are available when needed, TrustEstablishment includes a software agent called an intelligent collector. "Its job is to crawl the Web and collect whatever certificates are required to establish trust according to a particular trust policy," says Mass. For example, a doctor in the United States wishing to tap the resources of a hospital in Israel will access its Web site and present a certificate signed by the U.S. hospital. If the doctor's own hospital is unknown to the Israeli one, the latter's collector will automatically contact the U.S. hospital and request any certificates that might have been issued to it by other hospitals or health organizations. If the Israeli hospital knows at least two of them, it will grant access; if not, the collector will gather certificates from these other institutions, and so on, until it has obtained the required certificates.
The certificates, which are based on public-key cryptography, need not always reveal the holder's identity. Their main job is simply to establish a person's credentials. Unique among access control schemes, TrustEstablishment allows an online entity to associate a certificate holder with a particular role, such as being authorized to look at certain records, or even with multiple roles, such as both looking at a record and inserting comments.
Currently, the Haifa solution, in the form of a set of Java™ packages with an application programming interface, is available for downloading on IBM's alphaWorks® site. The solution includes an XML-based policy language that businesses can use to specify policies. The Haifa researchers have also developed a visual tool to edit policies and create a corresponding XML file. XML handling is achieved by the use of the XML Parser for Java from IBM's Tokyo Research Laboratory and Security is ensured by the use of the Crypto Framework—developed at IBM's Zurich Research Laboratory—which provides the basic cryptographic signature services. The person requesting access can obtain and present certificates using a standard Web browser.
Rowan Dordick is the editor of Think Research.
Screen and screen again
By Bruce Schechter
Until recently, readers who wanted to buy a new copy of Eye in the Sky by science fiction writer Philip K. Dick, or Janet Hobhouse's biography of Gertrude Stein, or thousands of other books, were in for a disappointment. The books are out of print, victims of the economics of publishing that make it unprofitable to print fewer than 5,000 copies of a book.
But the economic formulas have started to change. In 1998, using the InfoPrint® 4000 printer and software from IBM, Lightning Print (La Vergne, Tennessee), a subsidiary of Ingram Book Group, showed that it was possible to economically print a single copy of a book, initiating a new era of "publishing on demand." The only limitation was that these reincarnated books could not contain any photographs or illustrations, since these were too expensive to quickly scan and reproduce. But thanks to work by Jay Smith, a software developer at IBM's Printing Systems Division in Boulder, Colorado, and Ravi Rao and Gerry Thompson at IBM's Thomas J. Watson Research Center, this limitation has been overcome.
"If the book contains a halftone image, you have a problem," says Rao. Halftoning is the ubiquitous printing process that creates shades of gray by means of tiny dots that the eye blurs together. The dots of a halftone image are arranged in a periodic pattern known as the screen, and it is this pattern that makes scanning and reproducing halftone patterns so difficult. Each printer uses a slightly different screen. In fact, the two IBM InfoPrint 4000 machines used by Lightning Print—one prints 469 pages a minute and the other 708—each have slightly different screens. If the printer's screen frequency does not match the screen of the scanned image that it is printing, the result is a moiré pattern, a set of annoying dark stripes across the image.
The system invented by Rao and Smith eliminates this problem by converting the halftone images on the scanned page to a continuous form using a two-stage process. First an algorithm isolates images from text. Then another algorithm uses a mathematical technique known as a Fourier transform to determine the screen frequency. Once the screen frequency is known, a digital filter can be applied that carefully blurs the halftone dots together in much the same way that the eye does. The resulting image can now be printed on any printer, viewed on Web browsers and e-books, or used for any other purpose.
With the new software, a book can be scanned and converted to a printable form in about an hour, with only minimal supervision by an operator who handles any pages the program cannot. So far, the scanning system works only on black-and-white pictures. "The next step," says Rao, "is to apply these methods to color."
Bruce Schechter, a freelance writer who lives in Brooklyn, is the author of My Brain Is Open: The Mathematical Journeys of Paul Erdös.
