The approach described in the paper is similar to the idea of memory organization in a computer. In the computer memory there must be saved not only data workable, but also directions for processing itself. Only in case when with encryption a key appears as a memory: it contains both, information essential in the course of encryption (a key proper), and an instruction on the way of encryption should be carried out (an additional block of information). As a consequence of this the crypto-durability of the whole system increases. At the same time the postulate of used algorithm openness is not broken: in the course of encryption there are used open algorithms only, only a key is secret which bears in itself the block of secret information on an open algorithm superposition.