The system described in this section differs from the usual applications for smart cards in several basic aspects. These relate to the fundamental system architecture and data transmission mechanism, as well as how the cards are powered. This system is the ticket-free flight system of the German airline Lufthansa. It is based on contactless memory cards, which do not have to be inserted into a terminal. The basic system concept also differs from that of all other smart card applications described here, in that the cards are only used to identify the users, with all application data being held in the background system.For some time now, Lufthansa has been issuing frequent-flyer cards and cards for its bonus system. Originally, they used embossed cards and cards with magnetic stripes for automatic processing. In addition, certain types of cards could also be provided with a chip, so that they could be used with German public card phones and have a supplementary credit card function. This existing family of cards was to be extended by adding supplementary applications for boarding and ticketing in an upwardly compatible manner. In addition to the requirement for compatibility, a second objective was to make as few modifications as possible to existing systems. An equally important consideration was that the new cards should be easy for customers to use. In the ultimate stage of development, this would result in a multiapplication card with a magnetic stripe, embossing, a hologram, a memory chip with contacts and a contactless memory chip. Such a card could provide a large variety of functions without creating any compatibility problems with previously issued cards. Before the planned system-wide introduction of the newcards, a pilot projectwas conducted on the Frankfurt–Berlin route. The new cards were issued to 600 customers of all different types, and many thousands of flights were made on this route between May and December of 1995. To allow customers to use the cards, suitable automated service kiosks were installed at both airports. Each kiosk was a PC-based system with a touch-sensitive color screen, a printer and a transceiver for contactless smart cards.

Applications in the card
The new card offers customers a wide variety of applications. The following descriptions relate to the fully equipped version of the card. Naturally, there are also simpler versions, such as cards having only the functions of the contactless memory chip. With such a card, travelers can check themselves in at a service kiosk. This naturally leads to higher throughput, with shorter waiting times and/or faster processing. Lufthansa’s bonus system is also integrated into the contactless-chip version of the card, making it unnecessary to use any other card or enter additional information. Using suitable automated equipment located in the air terminal, a traveler can check in and receive a printed ‘boarding information’ form. This form contains all of the essential information regarding the booked flight, similar to what is on the actual ticket. If necessary, a seat selection for the booked flight can be made at the kiosk. Flights can also be booked by telephone using the number embossed on the card. In the future, Lufthansa plans to manage all of this without paper tickets, since all relevant information can be retrieved from the background system via the card. Naturally, this does not rule out making flight reservations by telephone or fax, which will continue to be possible. In addition to these functions, the card can also serve as a credit card by incorporating a hologram and a magnetic stripe with the necessary data. It is also possible to embed a contact-type chip in the ISO location. This is currently used to implant a phone-card chip.

The overall system
All of the applications based on the contactless chip are structured very simply with respect to the smart card. The card is used only for identification, with the memory chip being used to allow dynamic authentication by the background system.2 After authentication, all of the information stored in the card is read out. Currently, this consists of the customer number, customer name and customer profile.With this information, the background system can match the card to a particular person, after which the booking data, bonus system points and all other functions are available. The card is thus used only as a kind of key, with the data and mechanisms belonging to the various applications remaining in the background system. This has considerable advantages in this case, since the background system and all of its required databases, programs and interfaces are already well established. Another advantage of this system is the way it deals with lost or defective cards. This is a difficult issue, which up to now has always been neglected in other systems using multiapplication cards. If applications have been loaded into a card after personalization, when the cardholder receives a new card, he or she must individually contact all of the application providers in order to have them reload their applications into the card. Thanks to its centralized system architecture, the Lufthansa smart card system does not have this problem. If a card is lost or becomes defective, the customer receives a new card and the old card is blocked system-wide by means of its number. This does not require a large amount of logistical effort, since all airports served by Lufthansa have access to the necessary data via the well-established Lufthansa network.

The contactless card
The smart card has the internationally standard ID-1 format. The memory chip embedded in the card body uses inductive coupling, with a single coil for both power and data transfers. With this technology, the terminal can both read and write data at a distance of up to 10 cm. If the card is in an ordinary purse, it is even possible to exchange data with the terminal without removing the card from the purse. It is only necessary to hold the purse next to the terminal. Since the chip and the coil are both located inside the card, the graphic layout need not be affected by these components. Furthermore, contactless technology eliminates the problem of contact wear, since there simply aren’t any contacts. The typical transaction time between the terminal and the card in this system is around 100 ms, and a clock frequency of 13.56 MHz is used. The memory chip used (SLE 44R35) contains 1 kB of EEPROM and can be unilaterally authenticated by the outside world. Since presently only 48 bytes of data are stored in the memory (the customer number, customer name and customer profile), other applications could be incorporated in the future – although in this system, new applications naturally do not require additional memory in the smart card.

The field trial on the Frankfurt–Berlin routewas very successful. Nevertheless, implementation of the system in this form was not further pursued. Although this smart card application is atypical with regard to system architecture, it brings an interesting new perspective to the smart card world. Since the application data are located in the background system, all aspects related to protection of personal data are also shifted to this system. This means that data privacy legislation, regardless of which country is involved, cannot have any influence on the data stored in the card. This approach also circumvents the well-known memory space problems that arise when several applications are located in a single card, since the issue of which user is allowed to write which data to the card simply does not exist. The separation of applications on the card is also complete, since the system design avoids any possible interference between individual applications. Finally, it can be remarked that the data that are valuable to the system operator are always securely stored in his background system, rather than in smart cards where they can potentially become lost. This new system is also an exemplary illustration of a seamless transition from one card technology to the following one. This sort of ‘soft’ migration from one stage of technology to the next one is a very important consideration, since it preserves previous investments and avoids the need to construct an entirely new system.