Title:
関数型暗号システム及び方法
Document Type and Number:
Japanese Patent JP5841955
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a function type cryptography technique where a user prevents a key reissue attack which is the attack constituting a key having no orthodoxy, by combining two secret keys which are issued by some key generation station at different timing.SOLUTION: Other than a GID (a globally variable identifier), an identifier locally determined for each key generation station, namely an LID (a local identifier) is introduced. If cryptography can be configured so that the different LIDs cannot be combined for each other, a key reissue attack can be prevented. However, for a predicate variable created by other key generation station, decryption must be performed even if the different LIDs are combined for each other. Then, a predicate description mechanism using linear secret distribution of function type cryptography is skillfully used.
Inventors:
Hoshino Literature
Application Number:
JP2013008400A
Publication Date:
January 13, 2016
Filing Date:
January 21, 2013
Export Citation:
Assignee:
Nippon Telegraph and Telephone Corporation
International Classes:
H04L9/30; G09C1/00
Domestic Patent References:
| JP2012203182A | ||||
| JP2011141472A |
Foreign References:
| WO2010123122A1 |
Attorney, Agent or Firm:
Naoki Nakao
Yukio Nakamura
Yoshimura Munehiro
Yukio Nakamura
Yoshimura Munehiro