The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 12, 2006
Filed:
Jan. 15, 2002
Lauri Paatero, Helsinki, FI;
Lauri Paatero, Helsinki, FI;
Setec Oy, Vantaa, FI;
Abstract
The present invention relates to a device () comprising an input for receiving an input; calculation means (P) for producing a response (OUTPUT) in response to the input (INPUT) and a secret key (A) by utilizing a first predetermined function (f), and an output () for feeding said response (OUTPUT) further. In order for an attacker not be able to find out the secret key, the device further comprises a memory (M) in which the key-specific number (RND) is stored, and means for retrieving the key-specific number (RND) from the memory (M) and for feeding it to the calculation means (P') for carrying out predetermined calculation operations (f) on the basis of the key-specific number (RND) when producing said response (OUTPUT).