Technique for producing a privately authenticatable product copy indicia and for authenticating such an indicia

A method for authenticating an indicia associated with a corresponding product copy being installed on a computer, the indicia having a product copy identifier and an associated signature generated through a public-key cryptosystem, the public-key cryptosystem having a public key (PA), a private key (SA) and a third key (KA) wherein the third key is different from the first and second keys, the method comprising the steps, during installation of the product copy on a computer, of:

• obtaining the indicia for a product copy during installation of the product copy on a computer;
• and
• authenticating the signature contained in the indicia, comprising the steps of:
• extracting from the indicia, first and second portions of the signature, so as to yield extracted first and second portions of the signature, and the identifier;
• determining a new value of the first portion of the signature in response to a predefined generator value (g) selected from a plurality of points on an elliptic curve over a finite field, the identifier and the extracted first and second portions of the signature;
• and
• ascertaining whether the new value of the first portion matches the first extracted portion or not so as to signify whether the signature contained in the indicia is authentic or not;
• and
• if the signature is authentic or not, continuing the installation of the product on the computer or terminating the installation, respectively.

Apparatus for generating an indicia, containing an authentic signature, for association with a corresponding product copy, wherein the authentic signature is used in conjunction with a public-key cryptosystem having a public key (PA) and a private key (SA), the apparatus comprising:

• a processor;
• and
• a memory having computer executable instructions stored therein;
• wherein the processor, in response to the stored instructions:
• assigns a unique identifier, as message M, to the product copy;
• generates the authentic signature in response to the private key, the message, a predefined generator value (g) selected from a plurality of points on an elliptic curve over a finite field, and a third key (KA) different from the public and private keys and which is neither a public nor a private key within any key pair in an asymmetric key system;
• forms the indicia in response to the identifier and the authentic signature and
• associates the indicia with the product copy.

Apparatus for authenticating an indicia associated with a corresponding product copy being installed on a computer, the indicia having a product copy identifier and an associated signature generated through a public-key cryptosystem, the public-key cryptosystem having a public key (PA), a private key (SA) and a third key (KA) wherein the third key is different from the first and second keys, the apparatus comprising:

• a processor;
• and
• a memory having computer executable instructions stored therein;
• wherein the processor, in response to the stored instructions and during installation of the product copy on a computer:
• obtains the indicia for a product copy during installation of the product copy on a computer;
• extracts from the indicia, first and second portions of the signature, so as to yield extracted first and second portions of the signature, and the identifier;
• determines a new value of the first portion of the signature in response to a predefined generator value (g) selected from a plurality of points on an elliptic curve over a finite field, the identifier and the extracted first and second portions of the signature;
• ascertains whether the new value of the first portion matches the first extracted portion or not so as to signify whether the signature contained in the indicia is authentic or not;
• and
• if the signature is authentic or not, continues the installation of the product on the computer or terminates the installation, respectively.