International Business Machines Corporation

Walter Hanel

Klaus Rindtorff

Hermann R Bublitz

Martin Witzel

Michael Deindl

Albert Schaal

A method is disclosed in a number of embodiments, which use an identifier to control and limit the operation of a command and/or security code to one or more subdomains, such as directories, of a file structure. In one embodiment, the identifier is allocated to the command or to the security code. In another embodiment, the identifier is allocated to the subdomain. The security code includes a cryptographic key or a password.

Method for safely transferring data and applications onto a chipcard

The invention relates to a procedure for the certification of cryptographic keys for use in chipcards. In this procedure, a certification key and a certificate are transferred to the chipcard. The first part of the certificate includes the cryptographic key and the second part of the certificate includes a digital signature of the first part of the certificate. The digital certificate is subsequently checked by means of the certification key on the chipcard.

Certification of cryptographic keys for chipcards

A method and a system are proposed for increasing the data integrity on smartcards. In accordance with the invention a sequence of write processes on a smartcard is defined as a unit for which the integrity of the data to be written is ensured. The write process may involve the writing of data to one or more files. The data of an integrity unit i.e. a unit of data for which the integrity is to be ensured is preferably written to shadow memory. The method in accordance with the invention decreases considerably the likelihood that data will be corrupted through an error in writing the data on the smartcard. Data can be restored or completed through the interface of read-write units. The method in accordance with the invention can serve as a basis for maintaining data files external to the smartcard consistent with data on the smartcard.

Growing community of inventors

Holzgerlingen, Germany

Walter Hanel