Secure, swift cryptographic key exchange
US5835592A · kind A · utility
Inventors
Key dates
| Filing date | Sep 28, 1995 |
| Grant date | Nov 10, 1998 |
| Priority date | — |
| Expiry date | Sep 28, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L9/3093
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Using the present cryptographic key exchange protocol, a first of two cryptographic units selects quantities "A" and "B." That same unit then applies a mathematical function ".PHI..sub.1 " to A and B to compute a third quantity "C.". A and B and the function .PHI..sub.1 posses the property that knowing A or B, and C, and the function .PHI..sub.1, it is mathematically impossible to compute the unknown quantity B or A. The first unit then transmits A together C to the second unit while retaining B. The second unit selects a fourth quantity "D" and then applies a second mathematical function .PHI..sub.2 to A and D to compute a quantity "E" which the second unit transmits to the first unit while retaining D. The quantities A and D and the function .PHI..sub.2 must posses the property that knowing D and E, and the function .PHI..sub.2, it is mathematically impossible to compute the unknown quantity D. Then the second unit applies a third mathematical function ".PSI..sub.2 " to D and C to compute the key "K." The first unit upon receiving the quantity E then applies a fourth mathematical function .PSI..sub.1 to B and E to also compute the key K.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.