Extended card file system

摘要

An Extended SmartCard file system is proposed which resides in one flat file within the ISO file system of a SmartCard. A second file containing user information like size of the file system, owner information, and key fields is used to conFigure the file system driver dynamically. However, this file may be omitted if the file system driver is statically initialized. The nested file system of the present invention has the advantage that files can be fully dynamically accessed and edited without affecting the underlying ISO file layout, i.e. the outer fixed structure of the outer file system. Further, data integrity and consistency are achieved by a transaction oriented commit concept. Additionally, all security mechanisms of the underlying SmartCards in terms of data protection are fully maintained and are enhanced in cases of power loss or unexpected card removal as two distinct directories are provided for data management. <IMAGE>