Method and apparatus for providing upgrades in electricity meters

• US 5,715,390 A
• Filed: 11/30/1995
• Issued: 02/03/1998
• Est. Priority Date: 11/30/1995
• Status: Expired due to Term

• Current Assignee: Aclara Meters LLC (Hubbell, Inc.)
• Original Assignee: General Electric Company
• Inventors: Hershey, John E., Hoffman, Mark E.
• Primary Examiner(s): Beausoliel, Jr., Robert W.
• Assistant Examiner(s): Do, Luan C.
• Application Number:
  US08/564,971
• Time in Patent Office: 796 Days
• Field of Search: 340/870.02, 364/483, 364/464.04, 395/188.01, 395/186, 380/23, 380/25
• US Class Current: 726/20
• CPC Class Codes: G01R 21/1333 adapted for special tariff measuring
• CPC Class Codes: G01R 22/00 Arrangements for measuring time integral of electric power or current, e.g. electricity meters
• CPC Class Codes: G06Q 50/06 Energy or water supply
• CPC Class Codes: H04L 2209/56 Financial cryptography, e.g. electronic payment or e-cash
• CPC Class Codes: H04L 9/3226 using a predetermined code, e.g. password, passphrase or PIN network architectures or network communication protocols for supporting authentication of entities using passwords in a packet data network H04L63/083

Abstract

An electricity meter having a protected enabling scheme for activating meter options and upgrades is presented. The meter has a unique serial number, which includes bit-flags indicating which options have already been enabled, stored in the non-volatile RAM. Each option which is not enabled must be requested and a password verified before it can be utilized. At least one password is stored in a read protected location in the non-volatile RAM. The meter is in communication with a computer, e.g., a desktop or laptop type of computer. The password is generated by processing a secret software key and the unique serial number of the meter with an authentication algorithm. The computer is loaded with an upgrade software program, which includes the authentication algorithm. A hardware key which stores a secret software key is attached to a parallel port of the computer. The upgrade software program reads the serial number from the non-volatile RAM in the meter and reads the secret software key from the hardware key, then processes the read secret software key and the read unique serial number of the meter with the stored authentication algorithm to generate at least one password. The password along with an upgrade command are presented to the meter where they are compared to the read-protected password in the meter, and, if there is a match, then the upgrade command initiates codes in the meter to implement one or more stored options or upgrades.

Claims

1. A method of providing upgrades in an electronic electricity meter, the method comprising the steps of:

(1) pre-storing an upgrade in a memory of the meter, said upgrade requiring activation to allow use thereof,

(2) pre-storing a first password in a memory of the meter, said memory being external-read protected, and said first password being generated by processing a first software key and a serial number of said meter with a first authentication algorithm by a processor external to said meter,

(3) pre-storing said serial number in said memory of the meter, and,

(4) activating said upgrade to allow use thereof, said step of activating said upgrade comprising the steps of,

a. reading said serial number from said memory of the meter with an external processor,

b. reading a second software key from an external hardware device connected to said external processor, said second software key being the same as said first software key,

c. generating a second password with said external processor, by processing said second software key and said read serial number with a second authentication algorithm stored in a memory of said external processor, said second authentication algorithm being the same as said first authentication algorithm,

d. presenting said second password and an upgrade command stored in said memory of said external processor to the meter, and

e. comparing said first and second passwords in an internal processor of the meter, and in response to said upgrade command, activating said upgrade if said first and second passwords match.

2. The method of claim 1 wherein:

said first authentication algorithm comprises the steps of,

(1) initializing a first array of bytes with said first software key and said serial number to provide a first initialized array, said serial number including an option byte, and

(2) cycling said first initialized array to provide said first password; and

said second authentication algorithm comprises the steps of,

(1) initializing a second array of bytes with said second software key and said read serial number, including said option byte, to provide a second initialized array, and

(2) cycling said second initialized array to provide said second password.

3. The method of claim 2 wherein:

said step of initializing said first array comprises the steps of,

(1) placing said option byte in a first byte of said first array,

(2) placing bytes of said first software key into remaining sequential following odd or even bytes of said first array, and

(3) placing bytes of said serial number into remaining sequential following other odd or even bytes of said first array; and

said step of initializing said second array comprises the steps of,

(1) placing said option byte in a first byte of said second array,

(2) placing bytes of said second software key into remaining sequential following odd or even bytes of said second array, and

(3) placing bytes of said read serial number into remaining sequential following other odd or even bytes of said second array.

4. The method of claim 2 wherein:

said step of cycling said first initialized array comprises the steps of,

(1) computing a bit-by-bit modulo two sum of selected bytes in said first array,

(2) summing said computed bit-by-bit modulo two sum to a first constant to generate a first sum,

(3) end-around rotating said first sum,

(4) placing the contents of each byte of said first array in the previous byte of said first array, and

(5) repeating steps (1)-(4) of said step of cycling said first initialized array for a first plurality of cycles; and

said step of cycling said second initialized array comprises the steps of,

(1) computing a bit-by-bit modulo two sum of selected bytes in said second array,

(2) summing said computed bit-by-bit modulo two sum to a second constant to generate a second sum, said second constant being the same as said first constant,

(3) end-around rotating said second sum,

(4) placing the contents each byte of said second array in the previous bit of said second array, and

(5) repeating steps (1)-(4) of said step of cycling said second initialized array for a second plurality of cycles, said second plurality of cycles being the same as said first plurality of cycles.

5. The method of claim 2 wherein:

said step of cycling said first initialized array comprises the steps of,

(1) performing a bitwise exclusive-or on all the bytes in said first array,

(2) summing said bitwise exclusive-or to a first constant to generate a first sum,

(3) end-around rotating said first sum,

(4) placing the contents each byte of said first array in the previous bit of said first array, and

(5) repeating steps (1)-(4) of said step of cycling said first initialized array for a first plurality of cycles; and

said step of cycling said second initialized array comprises the steps of,

(1) performing a bitwise exclusive-or on all the bytes in said second array,

(2) summing said bitwise exclusive-or to a second constant to generate a second sum, said second constant being the same as said first constant,

(3) end-around rotating said second sum,

(4) placing the contents each byte of said second array in the previous bit of said second array, and

(5) repeating steps (1)-(4) of said step of cycling said second initialized array for a second plurality of cycles, said second plurality of cycles being the same as said first plurality of cycles.

6. The method of claim 1 wherein said step of activating said upgrade further comprises the step of:

(6) decrementing a counter each time an upgrade activated from said external processor.

7. The method of claim 1 wherein said external processor comprises a computer.

8. The method of claim 1 wherein said external hardware device comprises a hardware key.

9. A method of authentication comprising the steps of:

initializing an array of bytes with a software key and a serial number to provide an initialized array, said serial number including an option byte;

cycling said initialized array to provide a password; and

using said password for authentication.

10. The method of claim 9 wherein said step of initializing said array comprises the steps of:

(1) placing said option byte in a first byte of said array;

(2) placing bytes of said software key into remaining sequential following odd or even bytes of said array; and

(3) placing bytes of said serial number into remaining sequential following other odd or even bytes of said array.

11. The method of claim 9 wherein said step of cycling said initialized array comprises the steps of,

(1) computing a bit-by-bit modulo two sum of selected bytes in said array;

(2) summing said computed bit-by-bit modulo two sum to a constant to generate a sum;

(3) end-around rotating said sum;

(4) placing the contents each byte of said array in the previous bit of said array; and

(5) repeating steps (1)-(4) of said step of cycling said initialized array for a plurality of cycles.

12. The method of claim 9 wherein said step of cycling said initialized array comprises the steps of:

(1) performing a bitwise exclusive-or on all the bytes in said array;

(2) summing said bitwise exclusive-or to a constant to generate a sum;

(3) end-around rotating said sum;

(4) placing the contents each byte of said array in the previous bit of said array; and

(5) repeating steps (1)-(4) of said step of cycling said initialized array for a plurality of cycles.

13. An electricity meter comprising:

(1) electricity measuring circuitry for generating measured signals indicative of electricity being metered;

(2) a processor for responsive to said measured signals, and having a memory for storing;

signals including program signals defining a first executable algorithm for calculating electricity usage,

upgrade signals defining a second executable algorithm for performing an upgrade feature,

serial number signals indicative of a serial number of the meter, and

password signals used to allow activation of said upgrade feature, said password signals being external read protected, said password signals being generated by a processor with an authentication algorithm external to said meter by processing a software key and said serial number; and

(3) a port for communications with an external device.

14. The meter of claim 13 wherein said authentication algorithm comprises:

an array of bytes being initialized with said software key and said serial number, to provide an initialized array, said serial number including an option byte; and

said initialized array being cycled to provide a password.

15. The meter of claim 14 wherein said initialized array comprises:

said option byte in a first byte of said array;

bytes of said software key in remaining sequential following odd or even bytes of said array; and

bytes of said serial number in remaining sequential following other odd or even bytes of said array.

16. The meter of claim 14 wherein said cycling said initialized array comprises:

(1) computing a bit-by-bit modulo two sum of selected bytes in said array;

(2) summing said computed bit-by-bit modulo two sum to a constant to generate a sum;

(3) end-around rotating said sum;

(4) placing the contents each byte of said array in the previous bit of said array; and

(5) repeating (1)-(4) for a plurality of cycles.

17. The meter of claim 14 wherein said cycling said initialized array comprises:

(1) performing a bitwise exclusive-or on all the bytes in said array;

(2) summing said bitwise exclusive-or to a constant to generate a sum;

(3) end-around rotating said sum;

(4) placing the contents each byte of said array in the previous bit of said array; and

(5) repeating (1)-(4) for a plurality of cycles.

18. An apparatus for providing upgrades comprising:

an electricity meter comprising,

(1) electricity measuring circuitry for generating measured signals indicative of electricity being metered,

(2) a first processor responsive to said measured signals, having a first memory for storing first signals including first program signals defining a first executable algorithm for calculating electricity usage, storing second program signals defining a second executable algorithm for performing an upgrade feature, storing serial number signals indicative of a serial number of the meter, and storing first password signals indicative of a password, said first password signals being external read protected, said first password signals indicative of a password determined by processing a software key and said serial number with an authentication algorithm, and

(3) a port for communications;

upgrade apparatus external to said electricity meter comprising,

a. a second processor connected to said port of said meter for communicating with said meter to read said serial number therefrom

b. a hardware key having a second memory for storing software key signals indicative of said software key, said second processor having said hardware key connected thereto for communicating with said hardware key to read said software key therefrom, said processor having a third memory for storing second signals including third program signals defining a third executable algorithm for processing said read software key and said read serial number with said authentication algorithm to generate second password signals indicative of said password, said third memory for storing upgrade command signals, said second processor for communicating with said meter to present said second password signals and said upgrade command signals thereto; and

said first processor of said meter for communicating with said upgrade apparatus to read said second password signals and said upgrade command signals presented thereto, said first memory of said first processor for storing fourth program signals defining a fourth executable algorithm for comparing said first password signals with said second password signals, and applying said upgrade command signals to said second executable algorithm to activate said upgrade feature.

19. The apparatus of claim 18 wherein said authentication algorithm comprises:

an array of bytes being initialized with said software key and said serial number, to provide an initialized array, said serial number including an option byte; and

said initialized array being cycled to provide said password.

20. The apparatus of claim 19 wherein said initialized array comprises:

said option byte in a first byte of said array;

bytes of said software key in remaining sequential following odd or even bytes of said array; and

bytes of said serial number in remaining sequential following other odd or even bytes of said array.

21. The apparatus of claim 19 wherein said cycling said initialized array comprises:

(1) computing a bit-by-bit modulo two sum of selected bytes in said array;

(2) summing said computed bit-by-bit modulo two sum to a constant to generate a sum;

(3) end-around rotating said sum;

(4) placing the contents each byte of said array in the previous bit of said array; and

(5) repeating (1)-(4) for a plurality of cycles.

22. The apparatus of claim 19 wherein said cycling said initialized array comprises:

(1) performing a bitwise exclusive-or on all the bytes in said array;

(2) summing said bitwise exclusive-or to a constant to generate a sum;

(3) end-around rotating said sum;

(4) placing the contents each byte of said array in the previous bit of said array; and

(5) repeating (1)-(4) for a plurality of cycles.