| 摘要 |
<p>The invention relates to a method for protecting the authentication of a portable data carrier (1) relative to a reading device (2) via an unsecure communications path. Control information (Rl) is prepared by the portable data carrier (1) and is converted by the reading device (2) into a response message (S5) using a defined encoding technique and is transmitted for checking to the portable data carrier (1). Once it has been confirmed that the correct encoding technique was used, the data carrier authenticates the reading device (2). The encoding technique is based on the use of a variable key (T1*), which is preferably generated by a user (11) according to a formation specification that is known only to the user and is stored in the portable data carrier (1) and which is presented to the reading device (2). Alternatively, the variable key (T2*) is generated by the portable data carrier (1) on the basis of a random number and is made known to the user (11) following secure transmission via the reading device (2).</p> |
