Method and apparatus for providing upgrades in electricity meters
US5715390A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 30, 1995 |
| Grant date | Feb 3, 1998 |
| Priority date | — |
| Expiry date | Nov 30, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2209/56
- WIPO fieldMeasurement
- WIPO sectorInstruments
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 pass…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.