Patent ID: 8582763

Claim:
Method for generating information used in decoding encoded broadband data by one or more authorized users comprising the following steps: a. Providing the encoded broadband data for a plurality of users; b. Providing encoded or non-encoded key information, which is narrowband in comparison to the broadband data and which is individualized for one or more authorized users, exclusively in a decoding unit, wherein the narrowband key information is held in the decoding unit in a form which is not accessible for the authorized user, wherein at least parts of the narrowband key information are transferred into the decoding unit in an encoded form and are decoded there before the generation of broadband key information, and wherein the transfer of parts of the narrowband key information comprises specification of rights for usage of the broadband data by the user(s) for multiple or time limited usage; c. wherein the narrowband key information is usable for generating broadband key information from the narrowband key information in the decoding unit for the subsequent decoding of the encoded broadband data, wherein the data size of the narrowband key information is at least several thousand times smaller than the data size of the broadband data, and wherein the broadband key information has a size of essentially the same order of magnitude as the broadband data.