WO1996037065A1 - Secure one-way communication system - Google Patents

Secure one-way communication system Download PDF

Info

Publication number
WO1996037065A1
WO1996037065A1 PCT/NO1996/000117 NO9600117W WO9637065A1 WO 1996037065 A1 WO1996037065 A1 WO 1996037065A1 NO 9600117 W NO9600117 W NO 9600117W WO 9637065 A1 WO9637065 A1 WO 9637065A1
Authority
WO
WIPO (PCT)
Prior art keywords
receiver
message
transmitter
code
clock
Prior art date
Application number
PCT/NO1996/000117
Other languages
French (fr)
Inventor
Sigurd RØREN
Original Assignee
Defa A/S
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 Defa A/S filed Critical Defa A/S
Priority to AU58465/96A priority Critical patent/AU5846596A/en
Publication of WO1996037065A1 publication Critical patent/WO1996037065A1/en

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
    • G07C9/215—Individual registration on entry or exit involving the use of a pass the system having a variable access-code, e.g. varied as a function of time
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/06—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols the encryption apparatus using shift registers or memories for block-wise or stream coding, e.g. DES systems or RC4; Hash functions; Pseudorandom sequence generators
    • H04L9/065—Encryption by serially and continuously modifying data stream elements, e.g. stream cipher systems, RC4, SEAL or A5/3
    • H04L9/0656—Pseudorandom key sequence combined element-for-element with data sequence, e.g. one-time-pad [OTP] or Vernam's cipher
    • H04L9/0662—Pseudorandom key sequence combined element-for-element with data sequence, e.g. one-time-pad [OTP] or Vernam's cipher with particular pseudorandom sequence generator
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/12—Transmitting and receiving encryption devices synchronised or initially set up in a particular manner
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/32—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials
    • H04L9/3226—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials using a predetermined code, e.g. password, passphrase or PIN
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/32—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials
    • H04L9/3297—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials involving time stamps, e.g. generation of time stamps
    • 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
    • G07C2009/00238—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 the transmittted data signal containing a code which is changed
    • G07C2009/00253—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 the transmittted data signal containing a code which is changed dynamically, e.g. variable code - rolling code
    • 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
    • G07C2009/00793—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 Hertzian waves
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L2209/00—Additional information or applications relating to cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00
    • H04L2209/80—Wireless

Definitions

  • the present invention relates to a system comprising a method for use in transmitting and receiving one or more signals, especially signals comprising a message and a code which prevent unintentional use of said message.
  • the invention also relates to a transmitter and a receiver which are included in such a system.
  • the present invention is developed for the purpose of providing a system for secure one-way communication via radio.
  • a system comprises specifically a small radio transmitter which is attached to the key-ring of the user, and a radio receiver comprising control electronics mounted in the car which is at the disposal of the user.
  • the radio transmitter for example the door locks of the car are to be opened, possibly further func ⁇ tions of the car being triggered.
  • the system of today utilizes so-called code shift to protect communication against intruders.
  • code shift to protect communication against intruders.
  • the transmitter and receiver both generate the same vary ⁇ ing pseudo random code which is secret to the public.
  • the code will be transmitted together with the command to the receiver.
  • the receiver checks the received code with its own gene ⁇ rated code, and by conformity the command from the transmitter will be accepted.
  • a counter which has for the object to provide an alterable time code corresponding to the time code which is provid- ed by the counter on the transmitter side.
  • the object of the present invention is to provide a sys ⁇ tem alleviating the previously discussed problems.
  • said problems are resolved in a method of the type as stated in the pre ⁇ amble, which according to the invention is characterized in that to the message and/or code there is added a time information which in the transmitter is generated by a clock, and which in the receiver is checked by a syn- chronous clock.
  • the invention can be realized in that there is especially used code shift by means of a pseudo random (quasi random) generated code, which is trans- mitted together with said message including time informa ⁇ tion.
  • FIG. 1 there is illustrated a schematic principle diagram of a transmitter/receiver system where- in the present invention can find its application.
  • a key-ring comprising generally a transmitter 2, and more specifically a radio transmitter, a code generator, specifically a pseudo random code generator 3 as well as a clock 4.
  • a con ⁇ trol unit 5 for example mounted in a car, which control unit 5 inter alia comprises a receiver 6, a pseudo random code generator 7 and a clock 8.
  • the transmitter 2 can be of any appropriate type, not only a radio transmitter for transmitting electromagnetic waves, but also communica ⁇ tion signals based on sound, light, IR-waves, pressure waves, etc.
  • the system illustrated in Fig. 1 can for example be used in alarm systems for car as well as for operation of certain functions of the car, for example opening and closing of car locks.
  • Fig. 1 there is given ins ⁇ tructions for a system to be used for sending and receiv ⁇ ing one or more signals, specifically signals which com- prise a message or command, and a code included in said message and preventing unintentional use of said message.
  • a time information preferably in said command or message.
  • Both transmitter 2 and receiver 6 have "synchronous" clocks 4 and 8, respectively. When the command is transmitted from the transmitter 2 the time information will be included, and when the command is received in the receiver 6, the time in the command is compared to the clock 8 in the control unit 5 of the car. If the two points of time coincide, the command will be accepted by the control unit 5, and the command can then effect those functions which are assigned in said command or message.
  • the command will become obsolete after a given time interval, which can be determined by the transmitter 2 and the receiver 6.
  • a dishonest person will consequently not be able to register a message and use the latter in order to open the car prior to the obsoletion of said message.
  • the clocks 4 and 8, respectively, of the transmitter 2 and the receiver 6, respectively, can be synchronized at regular intervals, and the accuracy of the synchroniza- tion will state the time interval as previously dis ⁇ cussed. The accuracy can therefore appropriately be in the range of a second.

Abstract

The present invention relates to a system comprising a method and a transmitter receiver arrangement for use in transmitting and receiving a message including a code which prevents unintentional use of said message. For the object of obtaining better security against unauthorized registration of said message, it is according to the invention suggested that to the message there is added a time information which in the transmitter is generated by a clock, and which in the receiver is checked by a synchronous clock. Only when the time information in the received message corresponds to the clock of the receiver the message is accepted. The timing information can be encrypted using a pseudo random code, which is transmitted together with the message.

Description

Secure one-way communication system
Field of the invention
The present invention relates to a system comprising a method for use in transmitting and receiving one or more signals, especially signals comprising a message and a code which prevent unintentional use of said message. The invention also relates to a transmitter and a receiver which are included in such a system.
Background of the invention
The present invention is developed for the purpose of providing a system for secure one-way communication via radio. Such a system comprises specifically a small radio transmitter which is attached to the key-ring of the user, and a radio receiver comprising control electronics mounted in the car which is at the disposal of the user. By using the radio transmitter, for example the door locks of the car are to be opened, possibly further func¬ tions of the car being triggered.
Prior art
The system of today utilizes so-called code shift to protect communication against intruders. This means that the transmitter and receiver both generate the same vary¬ ing pseudo random code which is secret to the public. When the transmitter is activated, the code will be transmitted together with the command to the receiver. The receiver checks the received code with its own gene¬ rated code, and by conformity the command from the transmitter will be accepted.
The problem enfaced with this solution is that if a dis¬ honest person is able to register a command from the transmitter when this is outside the range of the receiver, this dishonestly registered command can be used to open the car, in the time span before the authorized user once more activates the transmitter towards the receiver. Consequently, there exists a time slot wherein the system is insecure.
From DE-A-42 18 500 (Borghetto) there is known a system for remote control of for example door locks in a vehicle, especially for operating an electronic control means. There is used a transmitter for transmitting a code and a receiver checking the code prior to outputting an operating signal. In order to render difficult the copying of the code, a time variable time code has been included in the transmitter and receiver. A counter on the transmitter side has for an object to provide a time code which alters according to a specific pattern and due to counting pulses received from a control unit, and being based on synchronous pulses supplied by a clocking means.
On the receiver side there is correspondingly provided a counter which has for the object to provide an alterable time code corresponding to the time code which is provid- ed by the counter on the transmitter side.
In other words, from the transmitter there will be trans¬ mitted a permanent identification code and a time code which is altered for example each tenth second. However, the time information according to said publication is included as a direct part of the coded message, which involves that according to the prior art there is achieved a relatively moderate security level.
Disclosure of the invention The object of the present invention is to provide a sys¬ tem alleviating the previously discussed problems.
According to the present invention said problems are resolved in a method of the type as stated in the pre¬ amble, which according to the invention is characterized in that to the message and/or code there is added a time information which in the transmitter is generated by a clock, and which in the receiver is checked by a syn- chronous clock.
Appropriately, the invention can be realized in that there is especially used code shift by means of a pseudo random (quasi random) generated code, which is trans- mitted together with said message including time informa¬ tion.
By including said time information in a pseudo random rotating code, there is achieved a totally very high security level.
Further features and advantages of the present invention will appear from the following description as well as from the appending patent claims.
Brief description of the drawing
In the attached Fig. 1 there is illustrated a schematic principle diagram of a transmitter/receiver system where- in the present invention can find its application.
Description of embodiments
In Fig. 1 there is illustrated a key-ring comprising generally a transmitter 2, and more specifically a radio transmitter, a code generator, specifically a pseudo random code generator 3 as well as a clock 4. In Fig. 1 there is also schematically illustrated a con¬ trol unit 5, for example mounted in a car, which control unit 5 inter alia comprises a receiver 6, a pseudo random code generator 7 and a clock 8.
It is to be understood that the transmitter 2 can be of any appropriate type, not only a radio transmitter for transmitting electromagnetic waves, but also communica¬ tion signals based on sound, light, IR-waves, pressure waves, etc.
The system illustrated in Fig. 1 can for example be used in alarm systems for car as well as for operation of certain functions of the car, for example opening and closing of car locks.
In other words, according to Fig. 1 there is given ins¬ tructions for a system to be used for sending and receiv¬ ing one or more signals, specifically signals which com- prise a message or command, and a code included in said message and preventing unintentional use of said message. What is specific in said system according to Fig. 1, wherein the present invention has been included, is that in addition to said code, especially a pseudo random code, there is added a time information, preferably in said command or message. Both transmitter 2 and receiver 6 have "synchronous" clocks 4 and 8, respectively. When the command is transmitted from the transmitter 2 the time information will be included, and when the command is received in the receiver 6, the time in the command is compared to the clock 8 in the control unit 5 of the car. If the two points of time coincide, the command will be accepted by the control unit 5, and the command can then effect those functions which are assigned in said command or message.
By means of the system illustrated in Fig. 1 the command will become obsolete after a given time interval, which can be determined by the transmitter 2 and the receiver 6. A dishonest person will consequently not be able to register a message and use the latter in order to open the car prior to the obsoletion of said message.
The clocks 4 and 8, respectively, of the transmitter 2 and the receiver 6, respectively, can be synchronized at regular intervals, and the accuracy of the synchroniza- tion will state the time interval as previously dis¬ cussed. The accuracy can therefore appropriately be in the range of a second.

Claims

P a t e n t c l a i m s
1. Method for use in transmitting and receiving one or more signals, especially signals comprising a message and a code which prevents unintentional use of said message, c h a r a c t e r i z e d i n that to the message and/or code there is added a time information which in the transmitter is generated by a clock, and which in the receiver is checked by a synchronous clock.
2. Method as claimed in claim 1, c h a r a c t e r i z e d i n that there is especially used code shift by means of a pseudo random (quasi ran¬ dom) generated code, which is transmitted together with said message including time information.
3. Method as claimed in claim 1 or 2, c h a r a c t e r i z e d i n that when the command is received in the receiver, said command is compared with the receiver clock, and upon coincidence between said two points of time the command will be accepted.
4. Method as claimed in any of the claim 1-3, c h a r a c t e r i z e d i n that said command becomes obsolete after a given time interval which can be determined by transmitter (2) and receiver (6) .
5. Method as claimed in any of the preceding claims, c h a r a c t e r i z e d i n that the accuracy of the synchronization is in the range of approximately 1 sec.
6. Transmitter and receiver for use in transmitting and receiving one or more signals, especially signals com¬ prising a message and a code which prevents unintentional used of said message, c h a r a c t e r i z e d i n that said transmitter (2) communicates with a clock (4) which generates a time information when the transmitter transmits a message/- command, and that said receiver (6) checks the message/- command in relation to a synchronous clock communicating with said receiver (6).
7. Transmitter as claimed in claim 6, c h a r a c t e r i z e d i n that said transmitter (2) communicates with a pseudo code generator (3) which generates a pseudo random (quasi random) generated code, and that said code is transmitted together with a time information provided by said clock (4) .
8. Receiver as claimed in claim 6 or 7, c h a r a c t e r i z e d i n that said receiver (6) is adapted together with said synchronous clock (8) and a pseudo random code generator (7) to comparing said received message/command and upon coincidence between said two points of time to accept said command/message.
9. Transmitter and receiver as claimed in any of the claims 6-8, c h a r a c t e r i z e d i n that said transmitter (2) and receiver (6) are adapted subsequent to a given time interval to detecting asynchronous messages/commands as obsolete.
10. Transmitter and receiver as claimed in any of the claims 6-9, c h a r a c t e r i z e d i n that said clock (4) which cooperates with said transmitter (2) and said clock (8) which cooperates with said receiver (6), have a syn¬ chronization within a time range of approximately 1 sec.
PCT/NO1996/000117 1995-05-18 1996-05-14 Secure one-way communication system WO1996037065A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU58465/96A AU5846596A (en) 1995-05-18 1996-05-14 Secure one-way communication system

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NO951965A NO951965L (en) 1995-05-18 1995-05-18 Transceiver system
NO951965 1995-05-18

Publications (1)

Publication Number Publication Date
WO1996037065A1 true WO1996037065A1 (en) 1996-11-21

Family

ID=19898218

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/NO1996/000117 WO1996037065A1 (en) 1995-05-18 1996-05-14 Secure one-way communication system

Country Status (3)

Country Link
AU (1) AU5846596A (en)
NO (1) NO951965L (en)
WO (1) WO1996037065A1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002050782A2 (en) * 2000-12-19 2002-06-27 Azoteq (Pty) Ltd Method of and apparatus for transferring data
EP2500872A1 (en) * 2011-03-08 2012-09-19 Openways Sas Secured method for controlling the opening of locking devices by means of a communication object such as a mobile phone
EP1423826B1 (en) * 2001-05-22 2014-07-09 Ericsson Inc. Security system

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4218500A1 (en) * 1991-06-07 1992-12-10 Trw Sipea Spa REMOTE CONTROL
DE4141766A1 (en) * 1991-12-18 1993-06-24 Skultety Ivan Electronic data transmission protection for remote control device - using synchronised time counting at transmitter and receiver to block operation by recorded remote control data signal
US5351293A (en) * 1993-02-01 1994-09-27 Wave Systems Corp. System method and apparatus for authenticating an encrypted signal
US5363448A (en) * 1993-06-30 1994-11-08 United Technologies Automotive, Inc. Pseudorandom number generation and cryptographic authentication
EP0636963A2 (en) * 1993-07-30 1995-02-01 International Business Machines Corporation Authentication system using one-time passwords

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4218500A1 (en) * 1991-06-07 1992-12-10 Trw Sipea Spa REMOTE CONTROL
DE4141766A1 (en) * 1991-12-18 1993-06-24 Skultety Ivan Electronic data transmission protection for remote control device - using synchronised time counting at transmitter and receiver to block operation by recorded remote control data signal
US5351293A (en) * 1993-02-01 1994-09-27 Wave Systems Corp. System method and apparatus for authenticating an encrypted signal
US5363448A (en) * 1993-06-30 1994-11-08 United Technologies Automotive, Inc. Pseudorandom number generation and cryptographic authentication
EP0636963A2 (en) * 1993-07-30 1995-02-01 International Business Machines Corporation Authentication system using one-time passwords

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002050782A2 (en) * 2000-12-19 2002-06-27 Azoteq (Pty) Ltd Method of and apparatus for transferring data
WO2002050782A3 (en) * 2000-12-19 2003-01-30 Azoteq Pty Ltd Method of and apparatus for transferring data
EP1423826B1 (en) * 2001-05-22 2014-07-09 Ericsson Inc. Security system
EP2500872A1 (en) * 2011-03-08 2012-09-19 Openways Sas Secured method for controlling the opening of locking devices by means of a communication object such as a mobile phone
US8793784B2 (en) 2011-03-08 2014-07-29 Openways Sas Secure method for controlling the opening of lock devices by means of a communicating object such as a mobile phone

Also Published As

Publication number Publication date
AU5846596A (en) 1996-11-29
NO951965D0 (en) 1995-05-18
NO951965L (en) 1996-11-19

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