Method of issuance and revocation of certificates of authenticity used in public key networks and other systems
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United States of America Patent
Stats
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Nov 9, 1993
Grant Date -
N/A
app pub date -
Mar 13, 1992
filing date -
Mar 13, 1992
priority date (Note) -
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Abstract
A technique for issuing and revoking user certificates of authenticity in a public key cryptography system, wherein certificates do not need expiration dates, and the inconvenience and overhead associated with routine certificate renewals are minimized or avoided entirely. A Certification Authority issues certificates as required, and issues a blacklist having a start date, an expiration date, and an entry for every invalid certificate issued after the start date. Users assume that every certificate issued prior to the blacklist start date is invalid, and that invalid certificates issued after the start date will be included in the current blacklist. A new blacklist is issued prior to expiration of the current one, and the blacklist start date is changed only when the blacklist becomes unmanageably long.
First Claim
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- 15 United States
- 10 France
- 8 Japan
- 7 China
- 5 Korea
- 2 Other
Patent Owner(s)
| Patent Owner | Address | |
|---|---|---|
| HEWLETT-PACKARD DEVELOPMENT COMPANY L P | 10300 ENERGY DRIVE SPRING TX 77389 |
International Classification(s)
Inventor(s)
| Inventor Name | Address | # of filed Patents | Total Citations |
|---|---|---|---|
| Kaufman, Charles W | Northborough, MA | 64 | 3512 |
| Perlman, Radia J | Acton, MA | 126 | 6267 |
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Maintenance Fees
| Fee | Large entity fee | small entity fee | micro entity fee | due date |
|---|
| Fee | Large entity fee | small entity fee | micro entity fee |
|---|---|---|---|
| Surcharge after expiration - Late payment is unavoidable | $700.00 | $350.00 | $175.00 |
| Surcharge after expiration - Late payment is unintentional | $1,640.00 | $820.00 | $410.00 |
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