A Personal and Portable Database Server: the CQL Card

Database applications and technologies are of central importance in many information systems a person may encounter. To obtain services, the end-users are required a smart card (plastic card containing a microcomputer), which is a device providing information about the user's identity and some related personal data. It can be updated and loaded with new data that will be used during further sessions. Moreover the data contained into the smart card can be used by other information systems, the data are carried away from a site to another. The individual mobility increases the need for a person to carry information about himself anywhere and at any time. For services providers, such as health professionals, it is essential to access to this information stored on several information systems. In many applicative areas, to provide different information systems linked and networked is a real challenge. Based on personal information about the bearer, the smart card is a key to access to different information systems and a mean to share and interchange data. The smart cards are evolving towards personal database functions. We briefly present the technology of smart cards, then we introduce a new approach : the CQL card (for Card Query Language). This card integrates the concepts of the Database Management Systems. Database engine is carried out by the card microcomputer, the card is a new database machine. It manages "users" entities which handle different "objects" according to their "privileges". CQL, a subset of SQL, is used to communicate with the card. Views enable sharing data among information systems. Access rights and privileges guarantee the data privacy. To ease the integration of this portable database we have implemented an ODBC driver enabling smart card connectivity with many applications and DBMS's. The smart card as a personal and mobile data server is a new support for databases, it involves new applications, such as health care cards or administrative document cards, and new ways of carrying and interchanging information.