Apparatus and method for performing KASUMI ciphering
US7212631B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 1, 2001 |
| Grant date | May 1, 2007 |
| Priority date | — |
| Expiry date | Aug 30, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2209/24
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Techniques for efficient KASUMI ciphering are disclosed. In one aspect, one KASUMI round for generating a fractional portion of the KASUMI cipher is deployed with appropriate feedback such that eight sequential rounds produce the KASUMI output. In another aspect, one third of the FO function is deployed with appropriate feedback such that three successive cycles produce the FO output. In yet another aspect, the FI function is deployed with appropriate feedback such that two subsequent cycles produce the FI output. In yet another aspect, a sub-key generator comprising two shift registers produces sub-keys for each round and sub-stage thereof in an efficient manner. These aspects, collectively, yield the advanced benefits of low area and low cost implementations of KASUMI with a simple user interface. Various other aspects of the invention are also presented.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.