Patent ID: 7999659

Claim:
A method for access control to at least one memory area of a passive and/or backscatter-based transponder, the method comprising: activating a first or at least one second identification within the transponder, based on an identification selection criterion; transmitting the activated identification upon a request by a reader unit to the reader unit, dividing at least one memory area of the transponder into memory blocks of a settable size; assigning access control information to a respective memory block; and releasing or blocking read and/or write access to a specific memory block based on the associated access control information and the identification selection criterion, wherein the access control information comprises two bits, wherein a first bit pattern, made up of the two bits, releases read and write access to the specific memory block regardless of whether the first identification or the at least one second identification is activated, wherein a second bit pattern, made up of the two bits, blocks read and write access to the specific memory block with an activated first identification and blocks with a deactivated first identification, wherein a third bit pattern, made up of the two bits, releases read and write access to the specific memory block with an activated second identification and blocks with a deactivated second identification, and wherein a fourth bit pattern, made up of the two bits, releases read access to the specific memory block and blocks write access, regardless of whether the first identification or the at least one second identification is activated.