Key management for encrypted packet based networks
US4965804A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 3, 1989 |
| Grant date | Oct 23, 1990 |
| Priority date | — |
| Expiry date | Feb 3, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L9/0891
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
In a packet based communication network 10, a key management center 20 is used to distribute cryptographic keys for either a switched virtual circuit or a permanent virtual circuit. The disclosed methods allow the key management center 20 to communicate directly with the data encryption/decryption devices (DE's) 14 even though they operate in a transparent mode (rather than a store and forward mode). This is accomplished by balancing link counters with calls to fictitious addresses and/or use of interrupt packets transferred between the DTE 12 and the DE 14. In permanent virtual circuits, the MAC of the last packet transmitted under the cold cryptographic key is exchanged to synchronize the key change.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.