Utility meter for metering a utility consumption and optimizing upstream communications and method for managing these communications

• US 10,250,575 B2
• Filed: 04/26/2017
• Issued: 04/02/2019
• Est. Priority Date: 02/02/2011
• Status: Active Grant

• Current Assignee: Nagravision SA (Kudelski SA)
• Original Assignee: Nagravision SA (Kudelski SA)
• Inventors: Le Buhan, Corinne, Nicolas, Christophe, Conus, Joel
• Primary Examiner(s): Syed, Nabil H
• Assistant Examiner(s): Eustaquio, Cal J
• Application Number:
  US15/498,107
• Publication Number:
  US 20170295146A1
• Time in Patent Office: 706 Days
• CPC Class Codes: G01D 4/002 Remote reading of utility meters
• CPC Class Codes: H04L 63/0435 wherein the sending and receiving network entities apply symmetric encryption, i.e. same key used for encryption and decryption cryptographic mechanisms or cryptographic arrangements for symmetric key encryption H04L9/06
• CPC Class Codes: H04L 9/0618 Block ciphers, i.e. encrypting groups of characters of a plain text message using fixed encryption transformation
• CPC Class Codes: H04L 9/0861 Generation of secret information including derivation or calculation of cryptographic keys or passwords
• CPC Class Codes: H04L 9/14 using a plurality of keys or algorithms
• CPC Class Codes: H04L 9/30 Public key, i.e. encryption algorithm being computationally infeasible to invert or user's encryption keys not requiring secrecy
• CPC Class Codes: H04L 9/3247 involving digital signatures
• CPC Class Codes: H04Q 2209/60 for transmitting utility meters data, i.e. transmission of data from the reader of the utility meter
• CPC Class Codes: H04Q 9/00 Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom
• CPC Class Codes: Y02B 90/20 Smart grids as enabling technology in buildings sector smart grids supporting the management or operation of end-user stationary applications in general, or like technologies with no associated climate change mitigation effect Y04S20/00
• CPC Class Codes: Y04S 20/30 Smart metering, e.g. specially adapted for remote reading

Abstract

A utility meter and method for metering consumption of at least one utility including: a metering unit, a communication unit for sending/receiving messages to/from a management center, a memory to store a unique identifier pertaining to the utility meter and a first key, an encryption unit for encrypting the utility consumption as a first cryptogram, a message generator for generating a utility message containing the first cryptogram, a key generator for generating a payload key to be used by the encryption unit for encrypting the utility consumption, a second cryptogram generated by the encryption unit by encrypting the payload key with the first key, the second cryptogram being intended to be included, by the message generator, at least once into the utility message to be sent to the remote management center.

Claims

1. A device comprising:

a data collection module configured to collect device data; and

a communication circuit configured to exchange encrypted messages with a plurality of remote utility management centers;

said encrypted messages including downstream messages received from said utility management centers and upstream messages transmitted to said utility management centers;

said device being configured to;

split said upstream messages into control messages and payload messages comprising the device data collected by the data collection module,

encrypt the device data of each of said payload messages as first cryptograms using a payload key shared with said remote utility management centers, and

encrypt each of said control messages as second cryptograms by encrypting the payload key using a first key specific to a single one of the plurality of remote utility management centers; and

said communication circuit being further configured to;

transmit said second cryptograms to a respective one of the remote utility management centers, and

transmit said first cryptograms to at least one of the plurality of remote utility management centers.

2. The device of claim 1, wherein the device is further configured to transmit said payload key to each of said remote utility management centers in a control message.

3. The device of claim 1, wherein each first key is a management center public key pertaining to said remote utility management center.

4. The device of claim 1, wherein said first key is derived from an initialization value and a secret key known by said device, said initialization value being received through an initialization message.

5. The device of claim 4, wherein said initialization message further comprises a signature for authenticating the initialization message and allowing a use of the initialization value in case of successful authentication.

6. The device of claim 4, wherein said initialization message further comprises a time stamp for checking the validity of the initialization message and allowing a use of the initialization value in case of successful validity.

7. The device of claim 1, wherein said device data comprise at least utility consumption values metered by a utility meter.

8. The device of claim 1, wherein said device is further configured to transmit said upstream messages according to a time basis defined by a command received by at least one of said utility management centers or a parameter from which said device can be identified.

9. The device of claim 1, wherein said device is a utility meter or a part of said utility meter.

10. A method for exchanging encrypted messages between a device, configured for collecting device data, and a plurality of remote utility management centers configured for processing said device data;

said encrypted messages including downstream messages received from said utility management centers and upstream messages transmitted to said utility management centers, the method comprising;

splitting said upstream messages by said device into control messages and payload messages comprising the device data collected by the data collection module;

encrypting the device data of each of said payload messages as first cryptograms using a payload key shared with said remote utility management centers;

encrypting each of said control messages as second cryptograms by encrypting the payload key using a first key specific to a single one of the plurality of remote utility management centers; and

transmitting said second cryptograms by said device to a respective one of the remote utility management centers and transmitting said first cryptograms by said device to at least of one of the plurality of remote utility management centers.

11. The method of claim 10, wherein said payload key is transmitted to each of said remote utility management centers in a control message.

12. The method of claim 10, wherein each first key is a management center public key pertaining to said remote utility management center.

13. The method of claim 10, wherein said first key is derived from an initialization value and a secret key known by said device, and said initialization value being received through an initialization message.

14. The method of claim 13, wherein said initialization message being emitted by a supervision center linked to the remote utility management centers to which said control messages can be transmitted.

15. The method of claim 13, wherein said initialization message is received by said device via one of said remote utility management centers.

16. The method of claim 13, wherein said initialization message further comprises a signature for authenticating the initialization message and allowing a use of the initialization value in case of successful authentication.

17. The method of claim 13, wherein said initialization message further comprises a time stamp for checking the validity of the initialization message and allowing a use of the initialization value in case of successful validity.

18. The method of claim 13, wherein the first key, derived from the initialization value and the secret key, is a symmetric session key.

19. The method of claim 13, wherein the initialization value received through the initialization message is encrypted using a symmetric initialization session key.

20. The method of claim 10, wherein said upstream messages being transmitted by said device according to a time basis defined by a command received by at least one of said utility management centers or a parameter from which said device can be identified.