DE2457027A1 - PROCEDURE FOR PROGRAMMING ARRANGEMENTS FOR GENERATING RANDOM BINARY STRINGS - Google Patents

Description

Licentia Patent-Verwaltungs-GmbH PT-BK / Wgr / kö

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Method for programming arrangements for generating random binary character strings

Random binary strings are used in modern information technology for a variety of purposes; e.g. as noise signals, as test signals for transmission lines, as ciphertext for encrypting information.

For the latter use cases, random binary strings of extremely long periods are required, which can be created with the help of a program at the same time, i.e. phase-locked at the sending and receiving locations.

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It is assumed that arrangements for the repeatable generation of random binary character strings the interested parties are known · Is the period of the delivered by such an arrangement Binary string extremely long, so in some cases only the starting position to be set on a case-by-case basis can be used result in a sufficiently high level of security, and the starting position would be the one to be kept secret Key.

In some of the known methods, the starting position is established by one consisting of two parts Key set, with a basic key from time to time, the additional key, for example, before the start of the transmitted message is changed. For example, it was proposed in DT-AS 1 237 366, depending on the initial state of key pulse generators from the result of the mixture of a first and a second piece of state information. Is to the first status information is stored on the transmit and receive side, the second is determined on the transmit side and transmitted unencrypted to the receiving end. That described in column 7 from line 45 and shown in FIG Embodiment of a key pulse generator supplies one that is solely dependent on the initial state Binary string as an excerpt from a single possible binary string with a long period. At a

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such procedures lead to similar status information to one another also to binary strings that are similar to one another, which make deciphering easier. The possible exclusion of a number of certain pieces of state information that are binary strings that are similar to one another reduces the number of different binary strings that can be generated and would require very cumbersome rules for creating the keys.

In the previously known methods and circuits, the law for the formation of binary character strings is alone given by the rigid circuit structure.

The object leading to the invention was to provide a method for programming arrangements for generating random binary character strings by means of which a plurality of mutually independent binary character strings for encrypting information

Can be provided.

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The prerequisite for the changing use of different Education laws, the structure of the arrangement with several levels connected in parallel and / or in series, whereby each stage can supply a random-like binary character sequence of shorter period, is in arrangements for

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Generating random-like binary strings of extremely long periods is generally given.

The inventive method for programming multi-stage arrangements for the repeatable generation of random ones Binary strings using a basic keyword and one that changes on a case-by-case basis Additional keyword is characterized in that the basic keyword is decisive for the initial state of the individual stages of the arrangement, and that the Additional keyword in connection with the basic keyword unites the links within the individual Levels and education keys controlling between the levels are created.

The arrangement controlled by different formation keys is equivalent to a number of different random number generators, of which only one is used on a case-by-case basis.

The basic keyword is known to everyone involved and can be set, for example, by means of a selector switch or from memories such as punch cards, punched strips or magnetic memories entered into the arrangement and entered by appointment be changed from time to time.

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The additional keyword can be redefined in a known manner on the sending side, e.g. for each message to be transmitted or generated by a random generator and transmitted unencrypted to the receiving end.

As described, the additional keyword creates a further keyword in conjunction with the basic keyword an education key. For example, the individual characters of the additional keyword can be decisive be in favor of which characters are taken from the basic keyword and combined to form the education key, or the key educational signs can be obtained by logically combining signs of the basic and the basic Additional keyword.

The individual stages of the arrangement generally contain multi-digit feedback shift registers or also multi-digit ones Binary counter. The individual digits of the registers and the Counters are set to a specific initial state before each transmission.

The characters of the education key can be used to control logic circuits in the individual levels of the arrangement will:

the limit addresses of the binary counters,

the selection of the taps at the outputs of the binary counter digits,

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the selection of one of several inputs of each shift register,

the selection of one of several possible outputs of each shift register, the selection of one of several possible taps on each shift register for one signal leading to the logic circuit in the feedback circuit,

the choice of logic circuit in the feedback network of the shift registers,

also the assigner circuits such as switching matrices inserted between the individual stages of the arrangement or multiple switch.

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Claims (3)

_ ₇ _ 2Λ57027 Claims lj Method for programming multi-level arrangements for the repeatable generation of random binary character strings using a basic keyword and an additional keyword which changes from case to case, characterized in that the basic keyword is decisive for the initial state of the individual levels of the arrangement, and that the additional keyword. in connection with the basic keyword a die Links created within the individual levels and between the levels controlling the education key. 2. The method according to claim 1, characterized in that the characters of the additional key word are decisive for the selection of individual ones that result in the education key Sign of the basic keyword. 3. The method according to claim 1, characterized in that The key educational signs are obtained by logically linking signs of the basic and the basic Additional keyword. BK 73/80 60SS24 / 0S3 7