1. A method for protecting an operation sequence executed by a portable data carrier from spying out, wherein the data carrier has at least a processor core, a main memory and a cache memory with a plurality of cache lines ( 28 .x), and wherein the processor core is configured to access, upon executing the operation sequence, at least two data values (v 1 , v 2 ,. .. , vn, n≧2), the method comprising: providing said plurality of cache lines ( 28 .x) and said at least two data values (v 1 , v 2 ,. .. , vn, n≧2) such that the at least two data values (v 1 , v 2 ,. .. , vn) occupy at least one cache line of said plurality of cache lines ( 28 .x) in the cache memory, and each of said at least two data values (v 1 , v 2 ,. .. , vn) are divided into several portions (vi j ); and providing, in each cache line of said plurality of cache lines ( 28 .x) containing a portion (vi j ) of a first data value (vi), a portion (vk j ) of every other data value (vk), such that for each cache line of said plurality of cache lines ( 28 .x), the occurrence of a cache miss or of a cache hit is independent of whether the first or a different data value (vk) is accessed, wherein the portable data carrier is a smart card or a chip module.