Cryptographic key update management method and apparatus
US8045713B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 30, 2004 |
| Grant date | Oct 25, 2011 |
| Priority date | — |
| Expiry date | Jul 12, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2209/60
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A method and apparatus is provided for consolidating cryptographic key updates, the consolidated update information enabling, for example, a returning member of a secure group who has been offline, to recover the current group key, at least in most cases. The unconsolidated key updates each comprise an encrypted key, corresponding to a node of a key hierarchy, that has been encrypted using a key which is a descendant of that node. The key updates are used to maintain a key tree with nodes in this tree corresponding to nodes in the key hierarchy. Each node of the key tree is used to store, for each encrypting key used in respect of the encrypted key associated with the node, the most up-to-date version of the encrypted key with any earlier versions being discarded. The key tree, or a subset of the tree, is then provided to group members.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.