Authentication method for keyless entry system
US5506905A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 10, 1994 |
| Grant date | Apr 9, 1996 |
| Priority date | — |
| Expiry date | Jun 10, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2209/84
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A system for remotely controlling a desired door locking or other function in a vehicle or other protected environment has a transmitter and receiver for communicating a message including a sequence number, the code of a selected function to be performed and an authenticator. An algorithm in the transmitter and in the receiver has a cryptographic key and a seed code. Each algorithm generates the authenticator as a function of both the seed code and the function code; if the authenticators are equal, the message is valid. Upon each transmission the seed code is updated and the sequence number is incremented. The receiver updates its seed code according to the transmitted sequence number to keep the algorithms in synchronism.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.