Title:
【発明の名称】鍵生成装置
Document Type and Number:
Japanese Patent JP2833747
Kind Code:
B2
Abstract:
PURPOSE: To prevent the occurrence of illegal resending by a third person by storing a group of integers and an integer corresponding to a communicating party, generating an integer depending upon time, generating a certificate to be sent to the communicating party based upon the integer group and both the integers, and generating a key from the integers of the integer groups and both the integers. CONSTITUTION: A random number (r) is generated, x=α (mod n) ins calculated from a group of integers (e), (n) read out from a user's card and C=hash (Time, x) is found out by using a previously determined hash function (hash). Where, Time is current time. Then y=S1 .α (mod d) is calculated based upon integers S1 , n obtained from the card and (x, y) is defined as a certificate. When an opposite user is a user (j), a key is generated by WK=Zij (mod n). Then c= hash (Time, x) for the received certificate (x, y) is calculated based upon the hash function. Whether IDj =y /x (mod n) or not is judged by using the value (c) and the group of integers e, n read our from the card. Since a key on the transmitting side is equal to a key on the receiving side, cipher communication using the key can be executed.
Inventors:
OKAMOTO EIJI
Application Number:
JP25902987A
Publication Date:
December 09, 1998
Filing Date:
October 13, 1987
Export Citation:
Assignee:
NIPPON DENKI KK
International Classes:
G09C1/00; H04L9/06; H04L9/08; H04L9/14; (IPC1-7): G09C1/00; H04L9/08
Attorney, Agent or Firm:
Naoki Kyomoto (2 outside)