Abstract: A security file system for a portable data carrier provides improved security for the data carrier and for data contained in files in the data carrier. Although the data carrier may be embodied to look and feel much like an ordinary credit card, it contains a computer and a programmable memory with operating power and input and output data provided through a contactless interface. In order to provide security for the data carrier, the security file system on the data carrier includes a stored access code for verifying the identity of an individual attempting to access the data carrier, and an appropriate routine for limiting the number of unsuccessful attempts to access the data carrier. The security file system is also configurable to include select ones of multiple stored access codes for enabling the retrieval and modification of data in corresponding select ones of the files. The routine similarly limits the number of unsuccessful attempts to access these files.

Abstract: A portable data carrier system provides improved security for files which support multiple applications, from custom repertory dialing to storage of individual medical and/or banking records. Included in the system is a portable data carrier which looks and feels much like an ordinary credit card. The portable data carrier, however, includes a computer and an electrically erasable field programmable read-only memory. Power for operation of the portable data carrier is provided from an associated station via a reader/writer. The reader/writer also couples data between the data carrier and the associated station. Operation of the data carrier is through an executive operating system that is accessed from the station via a set of commonly understood command primitives. These command primitives manipulate the files in the data carrier in accordance with security requirements.

Abstract: A file system for a portable data carrier provides improved security for files which support multiple applications, from custom repertory dialing to storage of individual medical and/or banking records. Although the portable data carrier looks and feels much like an ordinary credit card, it includes a computer and an electrically erasable programmable read-only memory. Power for operation of the portable data carrier is provided from an associated station via a reader/writer. The reader/writer also couples data between the data carrier and the associated station. The applications reside in multiple files in memory on the portable data carrier. Appropriate application software residing in the station, when accompanied by an appropriate password, enables the retrieval and modification of these files. A separate password is required for gaining access to each of designated levels of interaction between the portable data carrier and the associated station.