Secure electric anti-theft device, anti-theft system comprising one such device and method of matching electric devices

• US 20060103531A1
• Filed: 08/21/2003
• Published: 05/18/2006
• Est. Priority Date: 08/21/2002
• Status: Active Grant

• Current Assignee: Magnolia Licensing LLC (IP Edge LLC)
• Original Assignee: Thomson Licensing SA (Vantiva SA)
• Inventors: Diehl, Eric, Furon, Teddy, Chevreau, Sylvain
• Granted Patent: US 7,832,002 B2
• Time in Patent Office: Days
• US Class Current: 340/572.100
• CPC Class Codes: G06F 21/88 Detecting or preventing theft or loss
• CPC Class Codes: G08B 13/1418 Removal detected by failure in electrical connection between the appliance and a control centre, home control panel or a power supply
• CPC Class Codes: Y04S 40/20 Information technology specific aspects, e.g. CAD, simulation, modelling, system security

Abstract

The invention particularly relates to an electrical device for connection to a predetermined network containing at least one watchdog device. The electrical device comprises configuration means for authorising its operation in the presence of said watchdog device, where these configuration means are based on the recording of a watchdog device public identifier in storage means of the electrical device; means for identifying at least one watchdog device when the electrical device is connected to any network containing such a watchdog device, and means for disabling the electrical device if the watchdog device identified does not correspond to the watchdog device for which it was configured or if said network does not contain a watchdog device. The invention also concerns an antitheft system and a method for pairing devices.

Claims

1. Electrical device for connection to a predetermined network containing at least one watchdog device, where said electrical device comprises:

storage means,

configuration means for authorising its operation in the presence of said watchdog device,

means for identifying at least one watchdog device when the electrical device is connected to any network containing such a watchdog device; and

means for disabling the electrical device if the watchdog device identified does not correspond to the watchdog device for which it was configured or if said network does not contain a watchdog device, wherein the configuration means are suitable for recording a public identifier of the watchdog device for which the electrical device is configured, in the storage means.

2. Electrical device according to claim 1, wherein the identification means comprise means for interrogating any watchdog device to determine its public identifier.

3. Electrical device according to claim 1, wherein the identification means comprise means for authenticating the watchdog device for which it was configured.

4. Electrical device according to claim 3, wherein the authentication means implement a zero-knowledge challenge/response protocol.

5. Electrical device according to claim 1, wherein said device is in a state chosen from one of the elements of the assembly comprising a virgin state, a configured state for operating in the presence of at least one watchdog device and a blocked state, the configured state being obtained after activation of the configuration means and the blocked state being obtained after activation of the disabling means.

6. Electrical device according to claim 5, wherein it operates only when it is in the configured state.

7. Antitheft system comprising:

at least one network;

at least one watchdog device connected to the network and containing a public identifier and

at least one electrical device intended to be connected to said network and comprising;

storage means,

configuration means for authorising its operation in the presence of said watchdog device, wherein the configuration means are suitable for recording the public identifier of the watchdog device for which the electrical device is configured;

means for identifying at least one watchdog device when the electrical device is connected to an V network containing such a watchdog device; and

means for disabling the electrical device if the watchdog device identified does not correspond to the watchdog device for which it was configured or if said network does not contain a watchdog device.

8. Anti-theft system according to claim 7, wherein watchdog device comprises secure means for storing a secret identifier from which the public identifier is generated.

9. Antitheft system according to claim 8 wherein the network is chosen from among one of the elements of the group comprising an electric network, a digital transmission network and a telecommunications network.

10. Method for pairing a first and second device, where the second device is designed to be connected to a network that is connected to the first “

watchdog”

device said method comprising a step of configuration of the second device to authorize its operation only in the presence of the watchdog device wherein the step of configuration of the second device comprises the recording, in storage means of the second device, of a public identifier of the watchdog device.

11. Pairing method according to claim 10, wherein the second device is in a state selected from among one of the elements of the assembly made up of a virgin state of a state configured to operate in the presence of at least one watchdog device and a blocked state, and in that the configuration step contains a change in state of the second device, from the virgin to the configured state.

12. Pairing method according to claim 11, further comprising a step of disabling the second device when this device is connected to a watchdog device for which it was not configured, where this disabling step comprises a change of state of the second device, from the configured state to the blocked state.

13. Pairing method according to claim 11, further comprising a step of identifying a watchdog device connected to a network, when the second device is connected to this network.

14. Pairing method according to claim 13, wherein the identification step is triggered by one of the triggering events from the set of events constituted by a connection of the second device to the network, a start up of the second device and a regular or random identification program.

15. Pairing method according to claim 13 wherein the identification step comprises the authentication of the watchdog device.

16. Pairing method according to claim 15, wherein the authentication step is realised by the use of a zero-knowledge challenge/response protocol.

17. Pairing method according to claim 16, wherein, the watchdog device comprising means for secure storage of a secret identifier from which a public identifier is generated, the identification comprises a step of interrogating the watchdog device to determine its public identifier and the authentication comprises a series of steps during which the watchdog device proves to the electrical device that it knows the secret identifier using the zero-knowledge challenge/response protocol.

18. Pairing method according to claim 13, wherein if the identification step concludes that the network contains the watchdog device for which the second device was configured whereas the second device is in the blocked state, it is followed by a change in state of the second device from the blocked state to the configured state.