EP0154019A1 - Coding method for an electronic key - Google Patents

Coding method for an electronic key Download PDF

Info

Publication number
EP0154019A1
EP0154019A1 EP84115594A EP84115594A EP0154019A1 EP 0154019 A1 EP0154019 A1 EP 0154019A1 EP 84115594 A EP84115594 A EP 84115594A EP 84115594 A EP84115594 A EP 84115594A EP 0154019 A1 EP0154019 A1 EP 0154019A1
Authority
EP
European Patent Office
Prior art keywords
code
receiver
transmitter
reset
electronic key
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP84115594A
Other languages
German (de)
French (fr)
Other versions
EP0154019B1 (en
Inventor
Friedrich Dr. techn./Phys. Dannhäuser
Erwin Dipl.-Ing. Heuwieser (Fh)
Heinz Dipl.-Phys. Preissinger
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Siemens AG
Original Assignee
Siemens AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Siemens AG filed Critical Siemens AG
Publication of EP0154019A1 publication Critical patent/EP0154019A1/en
Application granted granted Critical
Publication of EP0154019B1 publication Critical patent/EP0154019B1/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G07—CHECKING-DEVICES
    • G07C—TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE
    • G07C9/00—Individual registration on entry or exit
    • G07C9/00174—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys
    • G07C9/00182—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys operated with unidirectional data transmission between data carrier and locks
    • G—PHYSICS
    • G07—CHECKING-DEVICES
    • G07C—TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE
    • G07C9/00—Individual registration on entry or exit
    • G07C9/20—Individual registration on entry or exit involving the use of a pass
    • G07C9/28—Individual registration on entry or exit involving the use of a pass the pass enabling tracking or indicating presence
    • G—PHYSICS
    • G07—CHECKING-DEVICES
    • G07C—TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE
    • G07C9/00—Individual registration on entry or exit
    • G07C9/00174—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys
    • G07C2009/00753—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys operated by active electrical keys
    • G07C2009/00769—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys operated by active electrical keys with data transmission performed by wireless means
    • G07C2009/00785—Electronically operated locks; Circuits therefor; Nonmechanical keys therefor, e.g. passive or active electrical keys or other data carriers without mechanical keys operated by active electrical keys with data transmission performed by wireless means by light
    • G—PHYSICS
    • G07—CHECKING-DEVICES
    • G07C—TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE
    • G07C2209/00—Indexing scheme relating to groups G07C9/00 - G07C9/38
    • G07C2209/06—Involving synchronization or resynchronization between transmitter and receiver; reordering of codes

Definitions

  • the invention relates to a method for code security in an electronic key, in particular for motor vehicles with a built-in central locking system, which consists of a transmitter which emits a coded infrared signal which is received by a receiver matched to the code, the code of Signals at the transmitter and receiver are automatically adjustable, and in which the transmitter sends a reset code after desynchronization or battery change in the transmitter or receiver.
  • a reset code is sent in the known method. This opens immediately or after the next key press.
  • the Reset-Sac 1 Gae / 27.02.1984 Code represents a security vulnerability, since unauthorized copying enables an unauthorized user to open the lock with the help of the reset code.
  • the object of the invention is therefore to develop the method of the type specified in the introduction in such a way that unauthorized opening is prevented with the aid of the reset code.
  • This object is achieved in that the reset code releases a lock controlled by the receiver for opening with a mechanical key.
  • the opening is only prepared by sending the reset code. This is done, for example, by the reset code triggering a control signal which electronically opens the lock. A relay only opens one bolt, after which the second bolt can be opened with the mechanical key. Simultaneously with this "partial" opening of the lock, the reset code synchronizes transmitter and receiver in a known manner, i.e. it sets the counter belonging to this key number in the receiver to the value of the counter in the key.
  • the "partial" opening of the lock can be carried out, for example, in that there are two outputs in the receiver, which can either assume the "H” or "L” state and are used to distinguish between “release of the mechanical key” and “full opening” can be. If the release is only partial, only one output is set to “L”, while when fully opened both outputs are "L".

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Lock And Its Accessories (AREA)

Abstract

1. A method of code safeguarding for an electronic key, in particular for motor vehicles with built-in central locking, which comprises a transmitter which transmits a coded infrared signal which is received by a receiver tuned to the code, where the code of the signal can be set automatically in the transmitter and the receiver, and where the transmitter transmits a reset code following desynchronization or following a battery change in the transmitter or the receiver, where the reset code releases a lock, operated by the receiver, for opening by a mechanical key.

Description

Die Erfindung betrifft ein Verfahren zur Code-Sicherung bei einem elektronischen Schlüssel, insbesondere für Kraftfahrzeuge mit eingebauter Zentralverriegelung, der aus einem Sender besteht, welcher ein codiertes Infrarot-Signal aussendet, das von einem auf den Code abgestimmten Empfänger aufgenommen wird, wobei der Code des Signals bei Sender und Empfänger automatisch verstellbar sind, und bei dem der Sender nach Desynchronisation oder Batteriewechsel im Sender bzw. Empfänger einen Reset-Code sendet.The invention relates to a method for code security in an electronic key, in particular for motor vehicles with a built-in central locking system, which consists of a transmitter which emits a coded infrared signal which is received by a receiver matched to the code, the code of Signals at the transmitter and receiver are automatically adjustable, and in which the transmitter sends a reset code after desynchronization or battery change in the transmitter or receiver.

Ein derartiges Verfahren ist aus der DE-A 32 34 538 und DE-A 32 34 539 bekannt. Dabei sind im Sender und Empfänger eine Anzahl von Code-Nummern gespeichert, wobei nach jedem Sende- und Empfangsvorgang im Sender und Empfänger eine neue übereinstimmende Code-Nummer selbsttätig eingestellt wird, was fortlaufend oder unter Verwendung eines Zufallsgenerators geschehen kann. Dadurch wird aus einer großen Anzahl von Möglichkeiten, bei beispielsweise 24 Bits 224 = 16 Mio., ein beliebiges Bitmuster ausgewählt, so daß ein unrechtmäßiger Gebrauch eines codierten Codes beispielsweise durch Kopieren, praktisch ausgeschlossen ist.Such a method is known from DE-A 32 34 538 and DE-A 32 34 539. A number of code numbers are stored in the transmitter and receiver, a new matching code number being set automatically in the transmitter and receiver after each transmission and reception operation, which can be done continuously or using a random number generator. As a result, an arbitrary bit pattern is selected from a large number of possibilities, for example 24 bits 2 24 = 16 million, so that unlawful use of a coded code, for example by copying, is practically impossible.

Um dabei auch nach Batteriewechsel im Sender (Batterie im Schlüssel) bzw. Empfänger (Kraftfahrzeugakkumulator) oder nach Desynchronisation (Code befindet sich außerhalb des Fangbereichs) das Schloß öffnen zu können, wird bei dem bekannten Verfahren ein Reset-Code gesendet. Dieser öffnet sofort oder nach dem nächsten Tastendruck. Der Reset-Sac 1 Gae / 27.02.1984 Code stellt eine Sicherheitslücke dar, da bei einem unberechtigten Kopieren ein unbefugter Benutzer in die Lage versetzt wird, das Schloß mit Hilfe des Reset-Codes zu öffnen.In order to be able to open the lock even after changing the battery in the transmitter (battery in the key) or receiver (motor vehicle accumulator) or after desynchronization (code is outside the catch range), a reset code is sent in the known method. This opens immediately or after the next key press. The Reset-Sac 1 Gae / 27.02.1984 Code represents a security vulnerability, since unauthorized copying enables an unauthorized user to open the lock with the help of the reset code.

Aufgabe der Erfindung ist es daher, das Verfahren der eingangs angegebenen Art derart weiterzubilden, daß das unberechtigte Öffnen mit Hilfe des Reset-Codes verhindert wird.The object of the invention is therefore to develop the method of the type specified in the introduction in such a way that unauthorized opening is prevented with the aid of the reset code.

Diese Aufgabe wird erfindungsgemäß dadurch gelöst, daß der Reset-Code ein vom Empfänger angesteuertes Schloß zum Öffnen mit einem mechanischen Schlüssel freigibt.This object is achieved in that the reset code releases a lock controlled by the receiver for opening with a mechanical key.

Damit wird der Vorteil erzielt, daß durch die Aussendung des Reset-Codes die Öffnung nur vorbereitet wird. Dies geschieht beispielsweise, indem der Reset-Code ein Steuersignal veranlaßt, welches das Schloß elektronisch öffnet. Dabei öffnet ein Relais nur einen Riegel, wonach der zweite Riegel mit dem mechanischen Schlüssel geöffnet werden kann. Gleichzeitig mit dieser "teilweisen" Öffnung des Schlosses synchronisiert der Reset-Code in bekannter Weise Sender und Empfänger, d.h. er setzt den zu dieser Schlüsselnummer gehörigen Zähler im Empfänger auf den Wert des Zählers im Schlüssel.This has the advantage that the opening is only prepared by sending the reset code. This is done, for example, by the reset code triggering a control signal which electronically opens the lock. A relay only opens one bolt, after which the second bolt can be opened with the mechanical key. Simultaneously with this "partial" opening of the lock, the reset code synchronizes transmitter and receiver in a known manner, i.e. it sets the counter belonging to this key number in the receiver to the value of the counter in the key.

Die "teilweise" Öffnung des Schlosses kann beispielsweise dadurch vorgenommen werden, daß im Empfänger zwei Ausgänge vorhanden sind, die entweder den Zustand "H" oder "L" annehmen können und zur Unterscheidung von "Freigabe des mechanischen Schlüssel" und "volles Öffnen" benutzt werden können. Bei nur teilweiser Freigabe wird nur ein Ausgang auf "L" gesetzt, während bei vollem Öffnen beide Ausgänge "L" sind.The "partial" opening of the lock can be carried out, for example, in that there are two outputs in the receiver, which can either assume the "H" or "L" state and are used to distinguish between "release of the mechanical key" and "full opening" can be. If the release is only partial, only one output is set to "L", while when fully opened both outputs are "L".

1 Patentanspruch1 claim

Claims (1)

Verfahren zur Code-Sicherung bei einem elektronischen Schlüssel, insbesondere für Kraftfahrzeuge mit eingebauter Zentralverriegelung, der aus einem Sender besteht, welcher ein codiertes Infrarotsignal aussendet, das von einem auf den Code abgestimmten Empfänger aufgenommen wird, wobei der Code des Signals bei Sender und Empfänger automatisch verstellbar sind, und bei dem der Sender nach Desynchronisation oder Batteriewechsel im Sender bzw. Empfänger einen Reset-Code sendet, dadurch gekennzeichnet, daß der Reset-Code ein vom Empfänger angesteuertes Schloß zum Öffnen mit einem mechanischen Schlüssel freigibt.Method of securing a code for an electronic key, in particular for motor vehicles with a built-in central locking system, which consists of a transmitter which emits a coded infrared signal which is received by a receiver matched to the code, the code of the signal being transmitted automatically by the transmitter and receiver are adjustable, and in which the transmitter sends a reset code after desynchronization or battery change in the transmitter or receiver, characterized in that the reset code releases a lock controlled by the receiver for opening with a mechanical key.
EP84115594A 1984-02-29 1984-12-17 Coding method for an electronic key Expired EP0154019B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19843407436 DE3407436A1 (en) 1984-02-29 1984-02-29 METHOD FOR SECURING THE CODE OF AN ELECTRONIC KEY
DE3407436 1984-02-29

Publications (2)

Publication Number Publication Date
EP0154019A1 true EP0154019A1 (en) 1985-09-11
EP0154019B1 EP0154019B1 (en) 1988-07-20

Family

ID=6229210

Family Applications (1)

Application Number Title Priority Date Filing Date
EP84115594A Expired EP0154019B1 (en) 1984-02-29 1984-12-17 Coding method for an electronic key

Country Status (2)

Country Link
EP (1) EP0154019B1 (en)
DE (2) DE3407436A1 (en)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4325137A1 (en) * 1993-07-27 1995-02-02 Rbr Computertechnik Gmbh Process for actuating closure mechanisms with the aid of identification means
US5841363A (en) * 1993-10-01 1998-11-24 Marquardt Gmbh Locking system especially for automobiles
US6108326A (en) * 1997-05-08 2000-08-22 Microchip Technology Incorporated Microchips and remote control devices comprising same
US6166650A (en) * 1991-05-29 2000-12-26 Microchip Technology, Inc. Secure self learning system
US6980655B2 (en) 2000-01-21 2005-12-27 The Chamberlain Group, Inc. Rolling code security system
US10652743B2 (en) 2017-12-21 2020-05-12 The Chamberlain Group, Inc. Security system for a moveable barrier operator
US10862924B2 (en) 2005-06-30 2020-12-08 The Chamberlain Group, Inc. Method and apparatus to facilitate message transmission and reception using different transmission characteristics
US10944559B2 (en) 2005-01-27 2021-03-09 The Chamberlain Group, Inc. Transmission of data including conversion of ternary data to binary data
US10997810B2 (en) 2019-05-16 2021-05-04 The Chamberlain Group, Inc. In-vehicle transmitter training
US11074773B1 (en) 2018-06-27 2021-07-27 The Chamberlain Group, Inc. Network-based control of movable barrier operators for autonomous vehicles
US11423717B2 (en) 2018-08-01 2022-08-23 The Chamberlain Group Llc Movable barrier operator and transmitter pairing over a network

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3636822C2 (en) * 1986-10-29 1993-12-23 Ruf Kg Wilhelm Electronic remote control device, in particular for central locking systems of motor vehicles
US6175312B1 (en) 1990-05-29 2001-01-16 Microchip Technology Incorporated Encoder and decoder microchips and remote control devices for secure unidirectional communication
US6690796B1 (en) 1995-05-17 2004-02-10 The Chamberlain Group, Inc. Rolling code security system
CA2193846C (en) 1995-05-17 2004-02-17 Bradford L. Farris Rolling code security system

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2168972A1 (en) * 1972-01-28 1973-09-07 Cheops
FR2441036A2 (en) * 1978-11-03 1980-06-06 Sachs Systemtechnik Gmbh MAGNETIC LOCK
EP0098437A2 (en) * 1982-07-09 1984-01-18 Hülsbeck & Fürst GmbH. & Co. KG Electronic locking device with key and lock parts interacting by means of electric pulses

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2168972A1 (en) * 1972-01-28 1973-09-07 Cheops
FR2441036A2 (en) * 1978-11-03 1980-06-06 Sachs Systemtechnik Gmbh MAGNETIC LOCK
EP0098437A2 (en) * 1982-07-09 1984-01-18 Hülsbeck & Fürst GmbH. & Co. KG Electronic locking device with key and lock parts interacting by means of electric pulses

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6166650A (en) * 1991-05-29 2000-12-26 Microchip Technology, Inc. Secure self learning system
DE4325137A1 (en) * 1993-07-27 1995-02-02 Rbr Computertechnik Gmbh Process for actuating closure mechanisms with the aid of identification means
US5841363A (en) * 1993-10-01 1998-11-24 Marquardt Gmbh Locking system especially for automobiles
US6108326A (en) * 1997-05-08 2000-08-22 Microchip Technology Incorporated Microchips and remote control devices comprising same
US6985472B2 (en) 1997-05-08 2006-01-10 Microchip Technology Incorporated Method of communication using an encoder microchip and a decoder microchip
US6980655B2 (en) 2000-01-21 2005-12-27 The Chamberlain Group, Inc. Rolling code security system
US11799648B2 (en) 2005-01-27 2023-10-24 The Chamberlain Group Llc Method and apparatus to facilitate transmission of an encrypted rolling code
US10944559B2 (en) 2005-01-27 2021-03-09 The Chamberlain Group, Inc. Transmission of data including conversion of ternary data to binary data
US10862924B2 (en) 2005-06-30 2020-12-08 The Chamberlain Group, Inc. Method and apparatus to facilitate message transmission and reception using different transmission characteristics
US11778464B2 (en) 2017-12-21 2023-10-03 The Chamberlain Group Llc Security system for a moveable barrier operator
US11122430B2 (en) 2017-12-21 2021-09-14 The Chamberlain Group, Inc. Security system for a moveable barrier operator
US10652743B2 (en) 2017-12-21 2020-05-12 The Chamberlain Group, Inc. Security system for a moveable barrier operator
US12108248B2 (en) 2017-12-21 2024-10-01 The Chamberlain Group Llc Security system for a moveable barrier operator
US11074773B1 (en) 2018-06-27 2021-07-27 The Chamberlain Group, Inc. Network-based control of movable barrier operators for autonomous vehicles
US11763616B1 (en) 2018-06-27 2023-09-19 The Chamberlain Group Llc Network-based control of movable barrier operators for autonomous vehicles
US12056971B1 (en) 2018-06-27 2024-08-06 The Chamberlain Group Llc. Network-based control of movable barrier operators for autonomous vehicles
US11423717B2 (en) 2018-08-01 2022-08-23 The Chamberlain Group Llc Movable barrier operator and transmitter pairing over a network
US11869289B2 (en) 2018-08-01 2024-01-09 The Chamberlain Group Llc Movable barrier operator and transmitter pairing over a network
US11462067B2 (en) 2019-05-16 2022-10-04 The Chamberlain Group Llc In-vehicle transmitter training
US10997810B2 (en) 2019-05-16 2021-05-04 The Chamberlain Group, Inc. In-vehicle transmitter training

Also Published As

Publication number Publication date
DE3407436A1 (en) 1985-08-29
EP0154019B1 (en) 1988-07-20
DE3472814D1 (en) 1988-08-25

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